Re: session replication/tomcat 5.5
Hi, we are trying to set up session replication using a database with the PersistentManager and a JDBCStore. Peter Rossbach stated that there is no alternative to multicasting. Is it because the PersistentManager is only experimental? And we have problems using the PersistentManager+JDBCStore because it does not persist the session data when a request completed but only in irregular intervals. When you have several servers accessing the same replication store you cannot be sure that your session data is up-to-date when one request is served by server A and the next is served by server B. I already asked for a solution for that problem in the posting How to configure session replication with a database from 13.11.2006 10:01. Regards Achim [EMAIL PROTECTED] wrote: Hi, I would also like hear more about this from horse mouths. We are also need to replicate session where servers are spread across in different countries. Is there anyway we could use DB server for storing replication? Because all the tomcat are using the same DB servers in my case. With warm regards, Mohan Narayanaswamy ISCI,Standard Chartered Scope International, 3F, Asia Bldg, #1, Haddows Road, Chennai Ph: +91 98417 10021 Fonenet: (India) 550 - 16814 Mirou, Antoine [EMAIL PROTECTED] 11/14/2006 08:09 PM Please respond to Tomcat Users List To: Tomcat Users List users@tomcat.apache.org cc: Subject:RE: session replication/tomcat 5.5 Hello, Could you please give an example of really big sites ? How do you organize your cluster (how many members/domains, ...) ? Do you use Farm-deployer ? Do you use session replication ? How do you manage/monitor the cluster ? Many questions, sorry, but I'm currently studying the possibility of setting up a cluster of tomcat 5.5 for a 99.99% available app with lots of user connexions, and I really don't feel confident of my ease with tomcat clustering... Thanks for your answers. Regards, Antoine -Message d'origine- De : Peter Rossbach [mailto:[EMAIL PROTECTED] Envoyé : mardi 14 novembre 2006 09:31 À : Tomcat Users List Objet : Re: session replication/tomcat 5.5 Am 13.11.2006 um 20:27 schrieb David O'Dell: Is anyone using session replication in production? Yes, at really big sites :-) Is there an alternative to using multicasting? No, but you can implement you own membership service. In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? Yes, but split your cluster into different domains. Use Apache/mod_jk = 1.2.19 with the domain attribute. The mod_jk loadbalancer can then route to the right backup. regards Peter - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: session replication/tomcat 5.5
Am 13.11.2006 um 20:27 schrieb David O'Dell: Is anyone using session replication in production? Yes, at really big sites :-) Is there an alternative to using multicasting? No, but you can implement you own membership service. In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? Yes, but split your cluster into different domains. Use Apache/mod_jk = 1.2.19 with the domain attribute. The mod_jk loadbalancer can then route to the right backup. regards Peter - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: session replication/tomcat 5.5
Hello, Could you please give an example of really big sites ? How do you organize your cluster (how many members/domains, ...) ? Do you use Farm-deployer ? Do you use session replication ? How do you manage/monitor the cluster ? Many questions, sorry, but I'm currently studying the possibility of setting up a cluster of tomcat 5.5 for a 99.99% available app with lots of user connexions, and I really don't feel confident of my ease with tomcat clustering... Thanks for your answers. Regards, Antoine -Message d'origine- De : Peter Rossbach [mailto:[EMAIL PROTECTED] Envoyé : mardi 14 novembre 2006 09:31 À : Tomcat Users List Objet : Re: session replication/tomcat 5.5 Am 13.11.2006 um 20:27 schrieb David O'Dell: Is anyone using session replication in production? Yes, at really big sites :-) Is there an alternative to using multicasting? No, but you can implement you own membership service. In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? Yes, but split your cluster into different domains. Use Apache/mod_jk = 1.2.19 with the domain attribute. The mod_jk loadbalancer can then route to the right backup. regards Peter - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Ce message et toutes les pièces jointes (ci-après le « message ») sont confidentiels et établis à l'intention exclusive de ses destinataires. Toute utilisation de ce message non conforme à sa destination, toute diffusion ou toute publication, totale ou partielle, est interdite, sauf autorisation expresse. Si vous recevez ce message par erreur, merci de le détruire sans en conserver de copie et d'en avertir immédiatement l'expéditeur. Internet ne permettant pas de garantir l'intégrité de ce message, la Caisse des Dépôts et Consignations décline toute responsabilité au titre de ce message s'il a été modifié, altéré, déformé ou falsifié. This email message and any attachments (the email) are confidential and intended only for the recipient(s) indicated. If you are not an intented recipient, please be advised that any use, dissemination, forwarding or copying of this email whatsoever is prohibited without Caisse des Depots et Consignations's prior written consent. If you have received this email in error, please delete it without saving a copy and notify the sender immediately. Internet emails are not necessarily secured, and Caisse des Depots et Consignations declines responsibility for any changes that may have been made to this email after it was sent. - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: session replication/tomcat 5.5
Hi, I would also like hear more about this from horse mouths. We are also need to replicate session where servers are spread across in different countries. Is there anyway we could use DB server for storing replication? Because all the tomcat are using the same DB servers in my case. With warm regards, Mohan Narayanaswamy ISCI,Standard Chartered Scope International, 3F, Asia Bldg, #1, Haddows Road, Chennai Ph: +91 98417 10021 Fonenet: (India) 550 - 16814 Mirou, Antoine [EMAIL PROTECTED] 11/14/2006 08:09 PM Please respond to Tomcat Users List To: Tomcat Users List users@tomcat.apache.org cc: Subject:RE: session replication/tomcat 5.5 Hello, Could you please give an example of really big sites ? How do you organize your cluster (how many members/domains, ...) ? Do you use Farm-deployer ? Do you use session replication ? How do you manage/monitor the cluster ? Many questions, sorry, but I'm currently studying the possibility of setting up a cluster of tomcat 5.5 for a 99.99% available app with lots of user connexions, and I really don't feel confident of my ease with tomcat clustering... Thanks for your answers. Regards, Antoine -Message d'origine- De : Peter Rossbach [mailto:[EMAIL PROTECTED] Envoyé : mardi 14 novembre 2006 09:31 À : Tomcat Users List Objet : Re: session replication/tomcat 5.5 Am 13.11.2006 um 20:27 schrieb David O'Dell: Is anyone using session replication in production? Yes, at really big sites :-) Is there an alternative to using multicasting? No, but you can implement you own membership service. In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? Yes, but split your cluster into different domains. Use Apache/mod_jk = 1.2.19 with the domain attribute. The mod_jk loadbalancer can then route to the right backup. regards Peter - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Ce message et toutes les pièces jointes (ci-après le « message ») sont confidentiels et établis à l'intention exclusive de ses destinataires. Toute utilisation de ce message non conforme à sa destination, toute diffusion ou toute publication, totale ou partielle, est interdite, sauf autorisation expresse. Si vous recevez ce message par erreur, merci de le détruire sans en conserver de copie et d'en avertir immédiatement l'expéditeur. Internet ne permettant pas de garantir l'intégrité de ce message, la Caisse des Dépôts et Consignations décline toute responsabilité au titre de ce message s'il a été modifié, altéré, déformé ou falsifié. This email message and any attachments (the email) are confidential and intended only for the recipient(s) indicated. If you are not an intented recipient, please be advised that any use, dissemination, forwarding or copying of this email whatsoever is prohibited without Caisse des Depots et Consignations's prior written consent. If you have received this email in error, please delete it without saving a copy and notify the sender immediately. Internet emails are not necessarily secured, and Caisse des Depots et Consignations declines responsibility for any changes that may have been made to this email after it was sent. - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] This email is confidential. If you are not the addressee tell the sender immediately and destroy this email without using, sending or storing it. Emails are not secure and may suffer errors, viruses, delay, interception and amendment. Standard Chartered PLC and subsidiaries (SCGroup) do not accept liability for damage caused by this email and may monitor email traffic.
RE: session replication/tomcat 5.5
From: Mark Hagger [mailto:[EMAIL PROTECTED] Subject: Re: session replication/tomcat 5.5 99.99% gives you a whole 3153 mins per year, or 52 hours, or 1 hour per week of operation per year. Your premise is well taken, but the math is a bit shaky. 99.99% uptime per week equates to 1 minute of downtime in that period, not one hour, which emphasizes you point even more. - Chuck THIS COMMUNICATION MAY CONTAIN CONFIDENTIAL AND/OR OTHERWISE PROPRIETARY MATERIAL and is thus for use only by the intended recipient. If you received this in error, please contact the sender and delete the e-mail and its attachments from all computers. - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: session replication/tomcat 5.5
Hi, Sorry to go slightly off the topic, but I have to express surprise (laugh) at the 99.99% availability bit. Its highly laudable to aim at that, indeed mobile phone operators claim to aim for, or even require, five 9's, ie 99.999%, which equates to a massive 315 minutes downtime per year (and between you and me I _know_ that mobile operators never even get close). 99.99% gives you a whole 3153 mins per year, or 52 hours, or 1 hour per week of operation per yearAnd thats not much to play with. As all of us who have tried it know that trying to make a system highly redundant so that there are no single points of failure necessarily makes the whole thing more complicated and thus if something does go wrong (2 switches die at once or something, followed by a disk array failure, and causing an unexpected knock on effect etc etc), you can suddenly find that your massively complex system has all fallen apart and takes a few hours to put back together Speaking from experience of the tomcat session replication issue, we use it and it works well, although in fact we have just 2 tomcat instances at this time. However, problems can occur if a server dies whilst there are a lot of active sessions, after recovery of the failed box trying to bring the server back into the group and thus attempting to copy all those active sessions back can impose surprisingly and dangerous load levels on the live server. On a few occasions this did actually grind the live server to a halt and we had to restart the entire system from cold, dumping all the live sessions. I'm still searching for the optimal configuration for this. Still, I wish you well in the 99.99% availability quest. Mark On Tuesday 14 November 2006 12:09, Mirou, Antoine wrote: Hello, Could you please give an example of really big sites ? How do you organize your cluster (how many members/domains, ...) ? Do you use Farm-deployer ? Do you use session replication ? How do you manage/monitor the cluster ? Many questions, sorry, but I'm currently studying the possibility of setting up a cluster of tomcat 5.5 for a 99.99% available app with lots of user connexions, and I really don't feel confident of my ease with tomcat clustering... Thanks for your answers. Regards, Antoine -Message d'origine- De : Peter Rossbach [mailto:[EMAIL PROTECTED] Envoyé : mardi 14 novembre 2006 09:31 À : Tomcat Users List Objet : Re: session replication/tomcat 5.5 Am 13.11.2006 um 20:27 schrieb David O'Dell: Is anyone using session replication in production? Yes, at really big sites :-) Is there an alternative to using multicasting? No, but you can implement you own membership service. In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? Yes, but split your cluster into different domains. Use Apache/mod_jk = 1.2.19 with the domain attribute. The mod_jk loadbalancer can then route to the right backup. regards Peter - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] Ce message et toutes les pièces jointes (ci-après le « message ») sont confidentiels et établis à l'intention exclusive de ses destinataires. Toute utilisation de ce message non conforme à sa destination, toute diffusion ou toute publication, totale ou partielle, est interdite, sauf autorisation expresse. Si vous recevez ce message par erreur, merci de le détruire sans en conserver de copie et d'en avertir immédiatement l'expéditeur. Internet ne permettant pas de garantir l'intégrité de ce message, la Caisse des Dépôts et Consignations décline toute responsabilité au titre de ce message s'il a été modifié, altéré, déformé ou falsifié. This email message and any attachments (the email) are confidential and intended only for the recipient(s) indicated. If you are not an intented recipient, please be advised that any use, dissemination, forwarding or copying of this email whatsoever is prohibited without Caisse des Depots et Consignations's prior written consent. If you have received this email in error, please delete it without saving a copy and notify the sender immediately. Internet emails are not necessarily secured, and Caisse des Depots et Consignations declines responsibility for any changes that may have been made to this email after it was sent. - To start a new
Re: session replication/tomcat 5.5
On Tuesday 14 November 2006 16:49, Caldarale, Charles R wrote: Your premise is well taken, but the math is a bit shaky. 99.99% uptime per week equates to 1 minute of downtime in that period, not one hour, which emphasizes you point even more. Ooops, how embarrassing, I calculated everything in seconds and then mysteriously wrote minutes all over the email. Probably didn't drink enough coffee today. Mark This email has been scanned for all known viruses by the MessageLabs SkyScan service. - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: session replication/tomcat 5.5
As a case study, I have, in production, 4 Dell 2850 servers (running Red Hat Enterprise V4.) Apache httpd on one, using JK for load balancing. The other three are running Tomcat in a 3-way multicast cluster, multicasting with replication on a private VLAN (192.168.x) The application accesses several DB servers running Oracle and MySQL, depending on the DB requested. Over time, this handles 2 requests per second average, with peaks at about 5-6 requests per second (Per Tomcat, so times 3). This does not begin to tax the Tomcat servers for memory or CPU. The bulk of the time is database latency. Our usage profile is extremely regular and predictable -- we service school districts and they mainly use it from 8 to 3 (local time.) This configuration has been very reliable and far-surpasses the system it replaced - based on IIS and JRun. HTH, Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Monday, November 13, 2006 2:27 PM To: Tomcat Users List Subject: session replication/tomcat 5.5 Is anyone using session replication in production? Is there an alternative to using multicasting? In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: session replication/tomcat 5.5
Good to hear that someone is using this. I want to try this out in my environment with 8 instances of tomcat each with around 2,500 sessions per instance. Does this sound feasible? Also how do you monitor the cluster status? Tim Lucia wrote: As a case study, I have, in production, 4 Dell 2850 servers (running Red Hat Enterprise V4.) Apache httpd on one, using JK for load balancing. The other three are running Tomcat in a 3-way multicast cluster, multicasting with replication on a private VLAN (192.168.x) The application accesses several DB servers running Oracle and MySQL, depending on the DB requested. Over time, this handles 2 requests per second average, with peaks at about 5-6 requests per second (Per Tomcat, so times 3). This does not begin to tax the Tomcat servers for memory or CPU. The bulk of the time is database latency. Our usage profile is extremely regular and predictable -- we service school districts and they mainly use it from 8 to 3 (local time.) This configuration has been very reliable and far-surpasses the system it replaced - based on IIS and JRun. HTH, Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Monday, November 13, 2006 2:27 PM To: Tomcat Users List Subject: session replication/tomcat 5.5 Is anyone using session replication in production? Is there an alternative to using multicasting? In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: session replication/tomcat 5.5
I forgot to mention that we peak at about 6000 sessions on the average day. The all-time max for 2006 is 6810 sessions. For monitoring, we do several things. 1) We use lambda probe 2) We use MRTG and some scripts to graph things that the manager will readily disclose, like requests, threads, sessions, etc. 3) We use MRTG and some built-in application statistics for application-specific statistics At some point, I will probably use lamdaprobe to populate MRTG graphs of the connection pools. Right now we don't really monitor them per se When you say sessions per instance keep in mind that sessions are shared across the cluster (or domain if so partitioned), otherwise it wouldn't be fault-tolerant. There is no pro-active alert if something is bad, other then the customers call the support line ;-) But we do have a large monitor in the engineering department visible to most of us with the vital MRTG graphs on display. Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 3:03 PM To: Tomcat Users List Subject: Re: session replication/tomcat 5.5 Good to hear that someone is using this. I want to try this out in my environment with 8 instances of tomcat each with around 2,500 sessions per instance. Does this sound feasible? Also how do you monitor the cluster status? Tim Lucia wrote: As a case study, I have, in production, 4 Dell 2850 servers (running Red Hat Enterprise V4.) Apache httpd on one, using JK for load balancing. The other three are running Tomcat in a 3-way multicast cluster, multicasting with replication on a private VLAN (192.168.x) The application accesses several DB servers running Oracle and MySQL, depending on the DB requested. Over time, this handles 2 requests per second average, with peaks at about 5-6 requests per second (Per Tomcat, so times 3). This does not begin to tax the Tomcat servers for memory or CPU. The bulk of the time is database latency. Our usage profile is extremely regular and predictable -- we service school districts and they mainly use it from 8 to 3 (local time.) This configuration has been very reliable and far-surpasses the system it replaced - based on IIS and JRun. HTH, Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Monday, November 13, 2006 2:27 PM To: Tomcat Users List Subject: session replication/tomcat 5.5 Is anyone using session replication in production? Is there an alternative to using multicasting? In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
RE: session replication/tomcat 5.5
Let me now ask my own question about this -- Lambda Probe is a great tool for inspecting your app's current state (and Tomcat's overall state.) Is it possible to get, using /probe or any other app (including tomcat's own manager) the current state of the connection pools in a machine-readable form (XML, one per line, CSV, etc.)? One that could easily be parsed with perl for consumption by MRTG? Lambda Probe's generated HTML isn't too easily parsed, at least for my novice perl skills. Tim -Original Message- From: Tim Lucia [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 4:29 PM To: 'Tomcat Users List' Subject: RE: session replication/tomcat 5.5 I forgot to mention that we peak at about 6000 sessions on the average day. The all-time max for 2006 is 6810 sessions. For monitoring, we do several things. 1) We use lambda probe 2) We use MRTG and some scripts to graph things that the manager will readily disclose, like requests, threads, sessions, etc. 3) We use MRTG and some built-in application statistics for application-specific statistics At some point, I will probably use lamdaprobe to populate MRTG graphs of the connection pools. Right now we don't really monitor them per se When you say sessions per instance keep in mind that sessions are shared across the cluster (or domain if so partitioned), otherwise it wouldn't be fault-tolerant. There is no pro-active alert if something is bad, other then the customers call the support line ;-) But we do have a large monitor in the engineering department visible to most of us with the vital MRTG graphs on display. Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 3:03 PM To: Tomcat Users List Subject: Re: session replication/tomcat 5.5 Good to hear that someone is using this. I want to try this out in my environment with 8 instances of tomcat each with around 2,500 sessions per instance. Does this sound feasible? Also how do you monitor the cluster status? Tim Lucia wrote: As a case study, I have, in production, 4 Dell 2850 servers (running Red Hat Enterprise V4.) Apache httpd on one, using JK for load balancing. The other three are running Tomcat in a 3-way multicast cluster, multicasting with replication on a private VLAN (192.168.x) The application accesses several DB servers running Oracle and MySQL, depending on the DB requested. Over time, this handles 2 requests per second average, with peaks at about 5-6 requests per second (Per Tomcat, so times 3). This does not begin to tax the Tomcat servers for memory or CPU. The bulk of the time is database latency. Our usage profile is extremely regular and predictable -- we service school districts and they mainly use it from 8 to 3 (local time.) This configuration has been very reliable and far-surpasses the system it replaced - based on IIS and JRun. HTH, Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Monday, November 13, 2006 2:27 PM To: Tomcat Users List Subject: session replication/tomcat 5.5 Is anyone using session replication in production? Is there an alternative to using multicasting? In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
Re: session replication/tomcat 5.5
Have a look at: http://yourserver:yourport/manager/jmxproxy?qry=*:* to find out about the available monitoring info. Once you find the beans you are interested in, you can make the query *:* more precise. Tim Lucia schrieb: Let me now ask my own question about this -- Lambda Probe is a great tool for inspecting your app's current state (and Tomcat's overall state.) Is it possible to get, using /probe or any other app (including tomcat's own manager) the current state of the connection pools in a machine-readable form (XML, one per line, CSV, etc.)? One that could easily be parsed with perl for consumption by MRTG? Lambda Probe's generated HTML isn't too easily parsed, at least for my novice perl skills. Tim -Original Message- From: Tim Lucia [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 4:29 PM To: 'Tomcat Users List' Subject: RE: session replication/tomcat 5.5 I forgot to mention that we peak at about 6000 sessions on the average day. The all-time max for 2006 is 6810 sessions. For monitoring, we do several things. 1) We use lambda probe 2) We use MRTG and some scripts to graph things that the manager will readily disclose, like requests, threads, sessions, etc. 3) We use MRTG and some built-in application statistics for application-specific statistics At some point, I will probably use lamdaprobe to populate MRTG graphs of the connection pools. Right now we don't really monitor them per se When you say sessions per instance keep in mind that sessions are shared across the cluster (or domain if so partitioned), otherwise it wouldn't be fault-tolerant. There is no pro-active alert if something is bad, other then the customers call the support line ;-) But we do have a large monitor in the engineering department visible to most of us with the vital MRTG graphs on display. Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 3:03 PM To: Tomcat Users List Subject: Re: session replication/tomcat 5.5 Good to hear that someone is using this. I want to try this out in my environment with 8 instances of tomcat each with around 2,500 sessions per instance. Does this sound feasible? Also how do you monitor the cluster status? Tim Lucia wrote: As a case study, I have, in production, 4 Dell 2850 servers (running Red Hat Enterprise V4.) Apache httpd on one, using JK for load balancing. The other three are running Tomcat in a 3-way multicast cluster, multicasting with replication on a private VLAN (192.168.x) The application accesses several DB servers running Oracle and MySQL, depending on the DB requested. Over time, this handles 2 requests per second average, with peaks at about 5-6 requests per second (Per Tomcat, so times 3). This does not begin to tax the Tomcat servers for memory or CPU. The bulk of the time is database latency. Our usage profile is extremely regular and predictable -- we service school districts and they mainly use it from 8 to 3 (local time.) This configuration has been very reliable and far-surpasses the system it replaced - based on IIS and JRun. HTH, Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Monday, November 13, 2006 2:27 PM To: Tomcat Users List Subject: session replication/tomcat 5.5 Is anyone using session replication in production? Is there an alternative to using multicasting? In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org
Re: session replication/tomcat 5.5
On 14.11.2006, at 22:44, Tim Lucia wrote: Let me now ask my own question about this -- Lambda Probe is a great tool for inspecting your app's current state (and Tomcat's overall state.) Is it possible to get, using /probe or any other app (including tomcat's own manager) the current state of the connection pools in a machine- readable form (XML, one per line, CSV, etc.)? One that could easily be parsed with perl for consumption by MRTG? Lambda Probe's generated HTML isn't too easily parsed, at least for my novice perl skills. You might want to have a look at Tomcat's JMX Proxy Servlet (part of the manager webapp, IIRC): http://tomcat.apache.org/tomcat-5.5-doc/manager-howto.html#What%20is% 20JMX%20Proxy%20Servlet The JMX Proxy Servlet is a lightweight proxy to get and set the tomcat internals. (Or any class that has been exposed via an MBean) Its usage is not very user friendly but the UI is extremely help for integrating command line scripts for monitoring and changing the internals of tomcat. If that's not enough, MX4J's HTTP adaptor serves XML, and lets you register custom XSLT stylesheets to transform the output. The default stylesheet transforms the XML to HTML. Regards, Dan -Original Message- From: Tim Lucia [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 4:29 PM To: 'Tomcat Users List' Subject: RE: session replication/tomcat 5.5 I forgot to mention that we peak at about 6000 sessions on the average day. The all-time max for 2006 is 6810 sessions. For monitoring, we do several things. 1) We use lambda probe 2) We use MRTG and some scripts to graph things that the manager will readily disclose, like requests, threads, sessions, etc. 3) We use MRTG and some built-in application statistics for application-specific statistics At some point, I will probably use lamdaprobe to populate MRTG graphs of the connection pools. Right now we don't really monitor them per se When you say sessions per instance keep in mind that sessions are shared across the cluster (or domain if so partitioned), otherwise it wouldn't be fault-tolerant. There is no pro-active alert if something is bad, other then the customers call the support line ;-) But we do have a large monitor in the engineering department visible to most of us with the vital MRTG graphs on display. Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 3:03 PM To: Tomcat Users List Subject: Re: session replication/tomcat 5.5 Good to hear that someone is using this. I want to try this out in my environment with 8 instances of tomcat each with around 2,500 sessions per instance. Does this sound feasible? Also how do you monitor the cluster status? Tim Lucia wrote: As a case study, I have, in production, 4 Dell 2850 servers (running Red Hat Enterprise V4.) Apache httpd on one, using JK for load balancing. The other three are running Tomcat in a 3-way multicast cluster, multicasting with replication on a private VLAN (192.168.x) The application accesses several DB servers running Oracle and MySQL, depending on the DB requested. Over time, this handles 2 requests per second average, with peaks at about 5-6 requests per second (Per Tomcat, so times 3). This does not begin to tax the Tomcat servers for memory or CPU. The bulk of the time is database latency. Our usage profile is extremely regular and predictable -- we service school districts and they mainly use it from 8 to 3 (local time.) This configuration has been very reliable and far-surpasses the system it replaced - based on IIS and JRun. HTH, Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Monday, November 13, 2006 2:27 PM To: Tomcat Users List Subject: session replication/tomcat 5.5 Is anyone using session replication in production? Is there an alternative to using multicasting? In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org
RE: session replication/tomcat 5.5
PERFECT! Thanks to you and Dan Baumann... -Original Message- From: Rainer Jung [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 4:59 PM To: Tomcat Users List Subject: Re: session replication/tomcat 5.5 Have a look at: http://yourserver:yourport/manager/jmxproxy?qry=*:* to find out about the available monitoring info. Once you find the beans you are interested in, you can make the query *:* more precise. Tim Lucia schrieb: Let me now ask my own question about this -- Lambda Probe is a great tool for inspecting your app's current state (and Tomcat's overall state.) Is it possible to get, using /probe or any other app (including tomcat's own manager) the current state of the connection pools in a machine-readable form (XML, one per line, CSV, etc.)? One that could easily be parsed with perl for consumption by MRTG? Lambda Probe's generated HTML isn't too easily parsed, at least for my novice perl skills. Tim -Original Message- From: Tim Lucia [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 4:29 PM To: 'Tomcat Users List' Subject: RE: session replication/tomcat 5.5 I forgot to mention that we peak at about 6000 sessions on the average day. The all-time max for 2006 is 6810 sessions. For monitoring, we do several things. 1) We use lambda probe 2) We use MRTG and some scripts to graph things that the manager will readily disclose, like requests, threads, sessions, etc. 3) We use MRTG and some built-in application statistics for application-specific statistics At some point, I will probably use lamdaprobe to populate MRTG graphs of the connection pools. Right now we don't really monitor them per se When you say sessions per instance keep in mind that sessions are shared across the cluster (or domain if so partitioned), otherwise it wouldn't be fault-tolerant. There is no pro-active alert if something is bad, other then the customers call the support line ;-) But we do have a large monitor in the engineering department visible to most of us with the vital MRTG graphs on display. Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Tuesday, November 14, 2006 3:03 PM To: Tomcat Users List Subject: Re: session replication/tomcat 5.5 Good to hear that someone is using this. I want to try this out in my environment with 8 instances of tomcat each with around 2,500 sessions per instance. Does this sound feasible? Also how do you monitor the cluster status? Tim Lucia wrote: As a case study, I have, in production, 4 Dell 2850 servers (running Red Hat Enterprise V4.) Apache httpd on one, using JK for load balancing. The other three are running Tomcat in a 3-way multicast cluster, multicasting with replication on a private VLAN (192.168.x) The application accesses several DB servers running Oracle and MySQL, depending on the DB requested. Over time, this handles 2 requests per second average, with peaks at about 5-6 requests per second (Per Tomcat, so times 3). This does not begin to tax the Tomcat servers for memory or CPU. The bulk of the time is database latency. Our usage profile is extremely regular and predictable -- we service school districts and they mainly use it from 8 to 3 (local time.) This configuration has been very reliable and far-surpasses the system it replaced - based on IIS and JRun. HTH, Tim -Original Message- From: David O'Dell [mailto:[EMAIL PROTECTED] Sent: Monday, November 13, 2006 2:27 PM To: Tomcat Users List Subject: session replication/tomcat 5.5 Is anyone using session replication in production? Is there an alternative to using multicasting? In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] - To start a new topic, e-mail: users@tomcat.apache.org
session replication/tomcat 5.5
Is anyone using session replication in production? Is there an alternative to using multicasting? In the doc http://tomcat.apache.org/tomcat-5.5-doc/cluster-howto.html It states This is an algorithm that is only efficient when the clusters are small. I have 6 tomcat instances behind a load balancer, is this still considered small? - To start a new topic, e-mail: users@tomcat.apache.org To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
