Re: [OT but still JSF]: Clustering, session replication, and database, too
Hi Tomcat/tomee session replication; memcached and custom session manager (hazelcast) solutions are different. Typically in some of them you accept SPoF, not in others. The perf are not the same too. Finally guarantees (synchronous or not persistence) can be different too. Mark info were consistent but adapted to his apps I think. The theorical solution is sometimes not enough... Was just to give some more inputs and dont believe in IT you have a single solution. PS: if tomee clustering has issues please help us working on it on trunk and tomee list Le 20 oct. 2013 07:30, José Luis Cetina maxtorz...@gmail.com a écrit : I have a early experience with a mini cluster 2 servers using tomee + memcached for session replication+ sticky session but using 1 only server for database (i mean i dont use db replication). My jsf apps (ear) are running in this mini cluster everithyng works fine except when i shutdown tomee for do a re deploy i always see an xhtml parser error. I could never configure it session replication with tomcat. In your web apps just use distributable tag in web.xml and all other are configuration. You can use memcached to not only session replication even thougth for savr information of your app and with this you can share information between your nodes and with this you dont persist information that could be transient. The result is incredible. As i sayed i could never configure session replication with tomcat, the only way i could do it is using memcached session replication. I dont know if anybody here have any experience with this. Regards Howard. El 19/10/2013 22:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html
Re: [OT but still JSF]: Clustering, session replication, and database, too
Ok Romain. Im not sure if is tomee issue of msm issue, but i will send you a mail with the info to the tomee mailing list. 2013/10/20 Romain Manni-Bucau rmannibu...@gmail.com Hi Tomcat/tomee session replication; memcached and custom session manager (hazelcast) solutions are different. Typically in some of them you accept SPoF, not in others. The perf are not the same too. Finally guarantees (synchronous or not persistence) can be different too. Mark info were consistent but adapted to his apps I think. The theorical solution is sometimes not enough... Was just to give some more inputs and dont believe in IT you have a single solution. PS: if tomee clustering has issues please help us working on it on trunk and tomee list Le 20 oct. 2013 07:30, José Luis Cetina maxtorz...@gmail.com a écrit : I have a early experience with a mini cluster 2 servers using tomee + memcached for session replication+ sticky session but using 1 only server for database (i mean i dont use db replication). My jsf apps (ear) are running in this mini cluster everithyng works fine except when i shutdown tomee for do a re deploy i always see an xhtml parser error. I could never configure it session replication with tomcat. In your web apps just use distributable tag in web.xml and all other are configuration. You can use memcached to not only session replication even thougth for savr information of your app and with this you can share information between your nodes and with this you dont persist information that could be transient. The result is incredible. As i sayed i could never configure session replication with tomcat, the only way i could do it is using memcached session replication. I dont know if anybody here have any experience with this. Regards Howard. El 19/10/2013 22:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html -- --- *SCJA. José Luis Cetina* ---
Re: [OT but still JSF]: Clustering, session replication, and database, too
Hello! I am also very interested in having more i.e. docs, examples and stuff for clustering across the tomee stack. The discussion came up on a jira some time ago and after that I asked Thomas to write a new post about it (First part was great!). For example this is something that sounds really interesting and I want to know more: * do not replicate the session over to other nodes! My scenarios are usually tomee with one war or tomcat with one war and JSF, CDI, JPA only. On 20 October 2013 05:48, Howard W. Smith, Jr. smithh032...@gmail.comwrote: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html
Re: [OT but still JSF]: Clustering, session replication, and database, too
Hey, JFYI: MyFaces+OWB on Tomcat with MSM is working fine. Don't know about TomEE. Regards, Thomas 2013/10/20 Karl Kildén karl.kil...@gmail.com Hello! I am also very interested in having more i.e. docs, examples and stuff for clustering across the tomee stack. The discussion came up on a jira some time ago and after that I asked Thomas to write a new post about it (First part was great!). For example this is something that sounds really interesting and I want to know more: * do not replicate the session over to other nodes! My scenarios are usually tomee with one war or tomcat with one war and JSF, CDI, JPA only. On 20 October 2013 05:48, Howard W. Smith, Jr. smithh032...@gmail.com wrote: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html
Re: [OT but still JSF]: Clustering, session replication, and database, too
@thomas: same on tomee + tomee has another integration for it, optimized for tomcat Le 20 oct. 2013 11:35, Thomas Andraschko andraschko.tho...@gmail.com a écrit : Hey, JFYI: MyFaces+OWB on Tomcat with MSM is working fine. Don't know about TomEE. Regards, Thomas 2013/10/20 Karl Kildén karl.kil...@gmail.com Hello! I am also very interested in having more i.e. docs, examples and stuff for clustering across the tomee stack. The discussion came up on a jira some time ago and after that I asked Thomas to write a new post about it (First part was great!). For example this is something that sounds really interesting and I want to know more: * do not replicate the session over to other nodes! My scenarios are usually tomee with one war or tomcat with one war and JSF, CDI, JPA only. On 20 October 2013 05:48, Howard W. Smith, Jr. smithh032...@gmail.com wrote: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html
Re: [OT but still JSF]: Clustering, session replication, and database, too
@romain do you have any article about it? Just for my interesst. What especially is optimized for tomcat? I may use TomEE in the future - if our customers allow this. 2013/10/20 Romain Manni-Bucau rmannibu...@gmail.com @thomas: same on tomee + tomee has another integration for it, optimized for tomcat Le 20 oct. 2013 11:35, Thomas Andraschko andraschko.tho...@gmail.com a écrit : Hey, JFYI: MyFaces+OWB on Tomcat with MSM is working fine. Don't know about TomEE. Regards, Thomas 2013/10/20 Karl Kildén karl.kil...@gmail.com Hello! I am also very interested in having more i.e. docs, examples and stuff for clustering across the tomee stack. The discussion came up on a jira some time ago and after that I asked Thomas to write a new post about it (First part was great!). For example this is something that sounds really interesting and I want to know more: * do not replicate the session over to other nodes! My scenarios are usually tomee with one war or tomcat with one war and JSF, CDI, JPA only. On 20 October 2013 05:48, Howard W. Smith, Jr. smithh032...@gmail.com wrote: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html
Re: [OT but still JSF]: Clustering, session replication, and database, too
smiling big... while I wrote OP (last night, my time), I did find Thomas's long discussion[1] with memcached-session-manager's committer/developer (Martin). and I remember Thomas said that Martin (the mail list) is 'very helpful', I think Thomas said that on primefaces forum. Romain, that discussion might help a bit. I did not read it yet. Thomas, I know that you remember that discussion...that's why you lightly-and-indirectly mentioned that in primefaces forum. :) [1] https://groups.google.com/forum/#!msg/memcached-session-manager/yCTsORhu_3c/noV_IvW-YF0J On Sun, Oct 20, 2013 at 5:34 AM, Thomas Andraschko andraschko.tho...@gmail.com wrote: JFYI: MyFaces+OWB on Tomcat with MSM is working fine.
Re: [OT but still JSF]: Clustering, session replication, and database, too
also, i'm still wondering about how database is replicated while clustering the app. On Sun, Oct 20, 2013 at 5:34 AM, Thomas Andraschko andraschko.tho...@gmail.com wrote: JFYI: MyFaces+OWB on Tomcat with MSM is working fine.
Re: [OT but still JSF]: Clustering, session replication, and database, too
romain, i have recognized and (gmail) star'red the mail list topics related to tomee clustering. have not tried yet, but i don't see (any) mention of how database is replicated while clustering tomee. On Sun, Oct 20, 2013 at 2:11 AM, Romain Manni-Bucau rmannibu...@gmail.comwrote: PS: if tomee clustering has issues please help us working on it on trunk and tomee list
Re: [OT but still JSF]: Clustering, session replication, and database, too
interesting response, Jose', thanks! for some time, I thought that it might be best to have separate server (tomee + @EJB/DTO's + tomcat's jdbc + database) which is/becomes the database tier. I guess I need to learn how to do/make remote calls to EJB server from JSF web layer like you are doing. i wonder if this is the typical/common/most-recommended-and-preferred solution. hmmm, avoid database replication. i have even seen tomcat committer (mark thomas slideshow/document on people.apache.org) mention that clustering your app should be avoided, if possible (or only used, if necessary). :) On Sun, Oct 20, 2013 at 1:30 AM, José Luis Cetina maxtorz...@gmail.comwrote: I have a early experience with a mini cluster 2 servers using tomee + memcached for session replication+ sticky session but using 1 only server for database (i mean i dont use db replication). My jsf apps (ear) are running in this mini cluster everithyng works fine except when i shutdown tomee for do a re deploy i always see an xhtml parser error. I could never configure it session replication with tomcat. In your web apps just use distributable tag in web.xml and all other are configuration. You can use memcached to not only session replication even thougth for savr information of your app and with this you can share information between your nodes and with this you dont persist information that could be transient. The result is incredible. As i sayed i could never configure session replication with tomcat, the only way i could do it is using memcached session replication. I dont know if anybody here have any experience with this. Regards Howard. El 19/10/2013 22:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html
Re: [OT but still JSF]: Clustering, session replication, and database, too
On Sun, Oct 20, 2013 at 7:07 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: hmmm, avoid database replication. honestly, I think HA-JDBC[1] (clustering the database) is all I really need, because my app is quite fast, and only bottleneck is database layer. I have seen David Blevins or Mark Struberg say that they reverted to caching much of the data from database (in memory, on startup, I guess/assume) to improve performance, but i wonder if caching the data is really (really) necessary/recommended... [1] http://ha-jdbc.github.io/
Re: [OT but still JSF]: Clustering, session replication, and database, too
DB replication basically works with the transaction log (IBM DB/2 terminology, in Oracle it's called transfer tables). Each update/insert/delete statement gets written into a file and you can pick this file up from another node. This secondary node then does exactly the same like the first node. See e.g. Master/Slave setup on MySQL. Means after a commit, after a few ms the secondary (slave) node has exactly the same info as the master node. And if the master node fails, then you can easily fall over to the slave node. This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. All other 'real' cluster solutions are really expensive and most of the times not worth the hassle imo ;) LieGrue, strub PS: usually clustering of Servlets are done by just 'pairing' up always 2 different servlet containers (tomcat nodes A+B, C+D) and have full session replication on them. Means whenever a request is done it will move the whole session content to the paired node. With the msm you can get away from this. - Original Message - From: Howard W. Smith, Jr. smithh032...@gmail.com To: MyFaces Discussion users@myfaces.apache.org Cc: Sent: Sunday, 20 October 2013, 12:56 Subject: Re: [OT but still JSF]: Clustering, session replication, and database, too also, i'm still wondering about how database is replicated while clustering the app. On Sun, Oct 20, 2013 at 5:34 AM, Thomas Andraschko andraschko.tho...@gmail.com wrote: JFYI: MyFaces+OWB on Tomcat with MSM is working fine.
Re: [OT but still JSF]: Clustering, session replication, and database, too
Try to avoid any remoting. Regardless whether remote EJB or even worse SOAP. The power it takes to transfer all your state to a different node is usually more than it takes to render your JSF pages. If you have performance issues then rather scale-out by adding another node and have a haproxy or any other load balancer with sticky session in front of it. LieGrue, strub - Original Message - From: Howard W. Smith, Jr. smithh032...@gmail.com To: MyFaces Discussion users@myfaces.apache.org Cc: Sent: Sunday, 20 October 2013, 13:07 Subject: Re: [OT but still JSF]: Clustering, session replication, and database, too interesting response, Jose', thanks! for some time, I thought that it might be best to have separate server (tomee + @EJB/DTO's + tomcat's jdbc + database) which is/becomes the database tier. I guess I need to learn how to do/make remote calls to EJB server from JSF web layer like you are doing. i wonder if this is the typical/common/most-recommended-and-preferred solution. hmmm, avoid database replication. i have even seen tomcat committer (mark thomas slideshow/document on people.apache.org) mention that clustering your app should be avoided, if possible (or only used, if necessary). :) On Sun, Oct 20, 2013 at 1:30 AM, José Luis Cetina maxtorz...@gmail.comwrote: I have a early experience with a mini cluster 2 servers using tomee + memcached for session replication+ sticky session but using 1 only server for database (i mean i dont use db replication). My jsf apps (ear) are running in this mini cluster everithyng works fine except when i shutdown tomee for do a re deploy i always see an xhtml parser error. I could never configure it session replication with tomcat. In your web apps just use distributable tag in web.xml and all other are configuration. You can use memcached to not only session replication even thougth for savr information of your app and with this you can share information between your nodes and with this you dont persist information that could be transient. The result is incredible. As i sayed i could never configure session replication with tomcat, the only way i could do it is using memcached session replication. I dont know if anybody here have any experience with this. Regards Howard. El 19/10/2013 22:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html
Re: [OT but still JSF]: Clustering, session replication, and database, too
interesting response, (and thanks) Mark! glad you feel that way about clustering (expensive and not worth the hassle), and scaling out the database for expensive queries/searches is definitely what I want, because I really think the tomee+ stack is performing very very well on my fast hardware. sadly, the (one) database for queries+writes (performance) definitely can be improved! will have to look into scaling out the database. thanks again! On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: DB replication basically works with the transaction log (IBM DB/2 terminology, in Oracle it's called transfer tables). Each update/insert/delete statement gets written into a file and you can pick this file up from another node. This secondary node then does exactly the same like the first node. See e.g. Master/Slave setup on MySQL. Means after a commit, after a few ms the secondary (slave) node has exactly the same info as the master node. And if the master node fails, then you can easily fall over to the slave node. This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. All other 'real' cluster solutions are really expensive and most of the times not worth the hassle imo ;) LieGrue, strub PS: usually clustering of Servlets are done by just 'pairing' up always 2 different servlet containers (tomcat nodes A+B, C+D) and have full session replication on them. Means whenever a request is done it will move the whole session content to the paired node. With the msm you can get away from this. - Original Message - From: Howard W. Smith, Jr. smithh032...@gmail.com To: MyFaces Discussion users@myfaces.apache.org Cc: Sent: Sunday, 20 October 2013, 12:56 Subject: Re: [OT but still JSF]: Clustering, session replication, and database, too also, i'm still wondering about how database is replicated while clustering the app. On Sun, Oct 20, 2013 at 5:34 AM, Thomas Andraschko andraschko.tho...@gmail.com wrote: JFYI: MyFaces+OWB on Tomcat with MSM is working fine.
Re: [OT but still JSF]: Clustering, session replication, and database, too
With Caching I meant stuff like all the things which do not change often. There is a big difference between 'almost static' data and between 'living data'. E.g. the User data can surely be cached for 30 minutes. How often do you add or change a new user in your system? Same for e.g. an amazon catalogue. This can be perfectly be cached for at least an hour without having to hit the database again. Of course not all data can be cached, but lots of things which are kind of 'configuration like' can. And this can take away a lot of hits from the database which is then free to serve other more important stuff. LieGrue, strub - Original Message - From: Howard W. Smith, Jr. smithh032...@gmail.com To: MyFaces Discussion users@myfaces.apache.org Cc: Sent: Sunday, 20 October 2013, 13:19 Subject: Re: [OT but still JSF]: Clustering, session replication, and database, too On Sun, Oct 20, 2013 at 7:07 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: hmmm, avoid database replication. honestly, I think HA-JDBC[1] (clustering the database) is all I really need, because my app is quite fast, and only bottleneck is database layer. I have seen David Blevins or Mark Struberg say that they reverted to caching much of the data from database (in memory, on startup, I guess/assume) to improve performance, but i wonder if caching the data is really (really) necessary/recommended... [1] http://ha-jdbc.github.io/
Re: [OT but still JSF]: Clustering, session replication, and database, too
On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. hmmm, had another question, if I remember it, then I can ask it later.
Re: [OT but still JSF]: Clustering, session replication, and database, too
wow, good point. I don't ever create new users in app. currently, the app is only 'for-office-use' only, but some day, i'm hoping the app will serve the customers of the business (and endusers have already mentioned some/different requirements where customers can login and do some stuff in the app, specific for customers, of course). i have already learned to cache 'static' data in @ApplicationScoped; a lot of lists that show up in selectOneMenu, etc..., are instantiated-and-cached on startup of the app (and inside the @ApplicationScoped bean). based on your response, I can definitely cache the user data and some of the 'static' data in the database. hmmm, i think I am doing that too, on a few of the tables, but I will have to check that. of course, omnifaces came up with a way for selectOneMenu to avoid the need to use @EJB to verify elements in the list (via selectone converter, or something like that)... i am not using that (yet). your idea, to cache the 'static' lists in database is definitely a better (performance) option than the omnifaces feature. evidently, i need to cache more data from my database in my @ApplicationScoped bean. i love that (CDI) @ApplicationScoped bean! On Sun, Oct 20, 2013 at 8:30 AM, Mark Struberg strub...@yahoo.de wrote: With Caching I meant stuff like all the things which do not change often. There is a big difference between 'almost static' data and between 'living data'. E.g. the User data can surely be cached for 30 minutes. How often do you add or change a new user in your system? Same for e.g. an amazon catalogue. This can be perfectly be cached for at least an hour without having to hit the database again. Of course not all data can be cached, but lots of things which are kind of 'configuration like' can. And this can take away a lot of hits from the database which is then free to serve other more important stuff. LieGrue, strub - Original Message - From: Howard W. Smith, Jr. smithh032...@gmail.com To: MyFaces Discussion users@myfaces.apache.org Cc: Sent: Sunday, 20 October 2013, 13:19 Subject: Re: [OT but still JSF]: Clustering, session replication, and database, too On Sun, Oct 20, 2013 at 7:07 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: hmmm, avoid database replication. honestly, I think HA-JDBC[1] (clustering the database) is all I really need, because my app is quite fast, and only bottleneck is database layer. I have seen David Blevins or Mark Struberg say that they reverted to caching much of the data from database (in memory, on startup, I guess/assume) to improve performance, but i wonder if caching the data is really (really) necessary/recommended... [1] http://ha-jdbc.github.io/
Re: [OT but still JSF]: Clustering, session replication, and database, too
just remembered-and-revised 2nd question, below... On Sun, Oct 20, 2013 at 8:35 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. this needs special handling in your app? can you please clarify? thanks!
Re: [OT but still JSF]: Clustering, session replication, and database, too
By the way im not using remote calls. All my apps are in the same ear with this i can inject my ejb local interface for calling methods in ejb. El 20/10/2013 07:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: just remembered-and-revised 2nd question, below... On Sun, Oct 20, 2013 at 8:35 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. this needs special handling in your app? can you please clarify? thanks!
Re: [OT but still JSF]: Clustering, session replication, and database, too
Hmmm, i thought you said that you have EAR on one server and database on separate server. are you running 2 tomee on same server; one tomee = EAR, another tomee = database? On Sun, Oct 20, 2013 at 11:52 AM, José Luis Cetina maxtorz...@gmail.comwrote: By the way im not using remote calls. All my apps are in the same ear with this i can inject my ejb local interface for calling methods in ejb. El 20/10/2013 07:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: just remembered-and-revised 2nd question, below... On Sun, Oct 20, 2013 at 8:35 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. this needs special handling in your app? can you please clarify? thanks!
Re: [OT but still JSF]: Clustering, session replication, and database, too
Ear with all my apps in each server (2 server each with their own ear) then each server insert/read in another unique db server. El 20/10/2013 16:09, Howard W. Smith, Jr. smithh032...@gmail.com escribió: Hmmm, i thought you said that you have EAR on one server and database on separate server. are you running 2 tomee on same server; one tomee = EAR, another tomee = database? On Sun, Oct 20, 2013 at 11:52 AM, José Luis Cetina maxtorz...@gmail.com wrote: By the way im not using remote calls. All my apps are in the same ear with this i can inject my ejb local interface for calling methods in ejb. El 20/10/2013 07:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: just remembered-and-revised 2nd question, below... On Sun, Oct 20, 2013 at 8:35 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. this needs special handling in your app? can you please clarify? thanks!
Re: [OT but still JSF]: Clustering, session replication, and database, too
so, db server is on a separate machine/server on the network, and each EAR is referencing the (one) db server via IP address? also, do you have an embedded db server (running inside of tomee and using tomcat jdbc pooling) or network db server/engine? On Sun, Oct 20, 2013 at 5:32 PM, José Luis Cetina maxtorz...@gmail.comwrote: Ear with all my apps in each server (2 server each with their own ear) then each server insert/read in another unique db server. El 20/10/2013 16:09, Howard W. Smith, Jr. smithh032...@gmail.com escribió: Hmmm, i thought you said that you have EAR on one server and database on separate server. are you running 2 tomee on same server; one tomee = EAR, another tomee = database? On Sun, Oct 20, 2013 at 11:52 AM, José Luis Cetina maxtorz...@gmail.com wrote: By the way im not using remote calls. All my apps are in the same ear with this i can inject my ejb local interface for calling methods in ejb. El 20/10/2013 07:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: just remembered-and-revised 2nd question, below... On Sun, Oct 20, 2013 at 8:35 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. this needs special handling in your app? can you please clarify? thanks!
Re: [OT but still JSF]: Clustering, session replication, and database, too
El 20/10/2013 19:34, Howard W. Smith, Jr. smithh032...@gmail.com escribió: so, db server is on a separate machine/server on the network, and each EAR is referencing the (one) db server via IP address? Yes 2 tomee instances each in separete server point to a third server that only serve as db server. Thats why y have clustering only in webapps and not in db. also, do you have an embedded db server (running inside of tomee and using tomcat jdbc pooling) or network db server/engine? I use tomcat jdbc pooling (tomee with defined connections in tomee.xml) On Sun, Oct 20, 2013 at 5:32 PM, José Luis Cetina maxtorz...@gmail.com wrote: Ear with all my apps in each server (2 server each with their own ear) then each server insert/read in another unique db server. El 20/10/2013 16:09, Howard W. Smith, Jr. smithh032...@gmail.com escribió: Hmmm, i thought you said that you have EAR on one server and database on separate server. are you running 2 tomee on same server; one tomee = EAR, another tomee = database? On Sun, Oct 20, 2013 at 11:52 AM, José Luis Cetina maxtorz...@gmail.com wrote: By the way im not using remote calls. All my apps are in the same ear with this i can inject my ejb local interface for calling methods in ejb. El 20/10/2013 07:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: just remembered-and-revised 2nd question, below... On Sun, Oct 20, 2013 at 8:35 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. this needs special handling in your app? can you please clarify? thanks!
Re: [OT but still JSF]: Clustering, session replication, and database, too
interesting. thanks Jose' On Sun, Oct 20, 2013 at 9:03 PM, José Luis Cetina maxtorz...@gmail.comwrote: El 20/10/2013 19:34, Howard W. Smith, Jr. smithh032...@gmail.com escribió: so, db server is on a separate machine/server on the network, and each EAR is referencing the (one) db server via IP address? Yes 2 tomee instances each in separete server point to a third server that only serve as db server. Thats why y have clustering only in webapps and not in db. also, do you have an embedded db server (running inside of tomee and using tomcat jdbc pooling) or network db server/engine? I use tomcat jdbc pooling (tomee with defined connections in tomee.xml) On Sun, Oct 20, 2013 at 5:32 PM, José Luis Cetina maxtorz...@gmail.com wrote: Ear with all my apps in each server (2 server each with their own ear) then each server insert/read in another unique db server. El 20/10/2013 16:09, Howard W. Smith, Jr. smithh032...@gmail.com escribió: Hmmm, i thought you said that you have EAR on one server and database on separate server. are you running 2 tomee on same server; one tomee = EAR, another tomee = database? On Sun, Oct 20, 2013 at 11:52 AM, José Luis Cetina maxtorz...@gmail.com wrote: By the way im not using remote calls. All my apps are in the same ear with this i can inject my ejb local interface for calling methods in ejb. El 20/10/2013 07:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: just remembered-and-revised 2nd question, below... On Sun, Oct 20, 2013 at 8:35 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. this needs special handling in your app? can you please clarify? thanks!
Re: [OT but still JSF]: Clustering, session replication, and database, too
how many concurrent users is your app servingnormally or at peak times? earlier, i think you mentioned response time is quite fast. did you throw fast/high-performance hardware at db server, so db server responds fasts to queries/updates? do you have any expensive queries or updates...that may cause other endusers to wait for a few seconds (or more)...if multiple users are using your app, concurrently? any (other db) performance issues that you'd like to share or you know can/should be optimized to improve response time since one database is serving 2 tomee/jsf/ear layer? On Sun, Oct 20, 2013 at 9:03 PM, José Luis Cetina maxtorz...@gmail.comwrote: El 20/10/2013 19:34, Howard W. Smith, Jr. smithh032...@gmail.com escribió: so, db server is on a separate machine/server on the network, and each EAR is referencing the (one) db server via IP address? Yes 2 tomee instances each in separete server point to a third server that only serve as db server. Thats why y have clustering only in webapps and not in db. also, do you have an embedded db server (running inside of tomee and using tomcat jdbc pooling) or network db server/engine? I use tomcat jdbc pooling (tomee with defined connections in tomee.xml) On Sun, Oct 20, 2013 at 5:32 PM, José Luis Cetina maxtorz...@gmail.com wrote: Ear with all my apps in each server (2 server each with their own ear) then each server insert/read in another unique db server. El 20/10/2013 16:09, Howard W. Smith, Jr. smithh032...@gmail.com escribió: Hmmm, i thought you said that you have EAR on one server and database on separate server. are you running 2 tomee on same server; one tomee = EAR, another tomee = database? On Sun, Oct 20, 2013 at 11:52 AM, José Luis Cetina maxtorz...@gmail.com wrote: By the way im not using remote calls. All my apps are in the same ear with this i can inject my ejb local interface for calling methods in ejb. El 20/10/2013 07:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: just remembered-and-revised 2nd question, below... On Sun, Oct 20, 2013 at 8:35 AM, Howard W. Smith, Jr. smithh032...@gmail.com wrote: On Sun, Oct 20, 2013 at 8:17 AM, Mark Struberg strub...@yahoo.de wrote: This can also be very helpful to 'scale out' in case you need performance: All write stuff is only performed on the master node, but expensive queries/searches might be performed on the n replication nodes. Of course this needs a special handling in your app, but allows to move the expensive queries away from your primary node. hmmm, had a question or two, or seeking clarification (or a bit more details or even a reference to a blog/article/document). 1. scale-out usually mean different physical servers? scaling out multiple databases on one physical server, usually (or I would assume) means that the hard drive becomes the bottleneck, if hard drive contain multiple databases. right? 2. this needs special handling in your app? can you please clarify? thanks!
Re: [OT but still JSF]: Clustering, session replication, and database, too
I have a early experience with a mini cluster 2 servers using tomee + memcached for session replication+ sticky session but using 1 only server for database (i mean i dont use db replication). My jsf apps (ear) are running in this mini cluster everithyng works fine except when i shutdown tomee for do a re deploy i always see an xhtml parser error. I could never configure it session replication with tomcat. In your web apps just use distributable tag in web.xml and all other are configuration. You can use memcached to not only session replication even thougth for savr information of your app and with this you can share information between your nodes and with this you dont persist information that could be transient. The result is incredible. As i sayed i could never configure session replication with tomcat, the only way i could do it is using memcached session replication. I dont know if anybody here have any experience with this. Regards Howard. El 19/10/2013 22:49, Howard W. Smith, Jr. smithh032...@gmail.com escribió: I had a question or two, since I have been reading Java Summit - Pitfalls in EE[1] provided by Mark Struberg while having a discussion on tomee user list. The following page stated the following: Page 134 Clustering * We use 'asymmetric clustering' * use sticky sessions * backup away the session to a memcached after each request * do not replicate the session over to other nodes! * Session-Replication always in node pairs. * only restore the session from the memcached if a failover happened * msm can be integrated into OWB: http://code.google.com/p/memcached-session-manager/ Since it says, 'We use asymmetric clustering' and other suggestions were made, I found it appropriate to direct my question(s) to MyFaces 'JSF' user list and committers. is there some type of blog (or two or three) available that discuss how to properly cluster a tomcat/tomee/openwebbeans/myfaces JSF web app? also, how is the database replicated? I don't ever see database cluster/replication discussed by JSF developers; i recently had to search for database cluster and saw 'replication', which is something i have not had to worry about since my previous work involved database teams while i was doing front-end/GUI software. now that i am doing java ee and jsf, i would love to know how to do database clustering and/or replicating database while clustering JSF webapp. Of course, right now, i only have one tomee which references 'apache' derby (which is performing well, but I would love to get my feet wet and cluster my web app + database). i did search derby's mail list archives and i learned about sequioa and HA-JDBC (High-Availability JDBC). i was hoping to get an answer from MyFaces 'JSF' users/committers...based on their experience. I think someone told me that they use mysql (clustering); my preference is still 'apache' derby (smile). please remember, i'm wondering if any blogs are available that discuss clustering tomcat (preference = tomee) + JSF web app (with database) + memcached session manager. Thomas has already started writing a blog[2] about this. I'm looking forward to seeing sample config for it all (if available). :) [1] http://people.apache.org/~struberg/eesummit2013/Java%20EE%20Summit%20-%20pitfalls%20in%20EE.pdf [2] http://tandraschko.blogspot.com/2013/09/session-replication-clustering-failover.html
