MC, In my test configuration, I believe the current and future requests would error out. I only have the Witango client loaded on one server and if it died or the server failed, it wouldn't be able to serve requests to ANY of the Witango services.
I would be curious to know how often the Witango client fails. For me it seems to be the Witango service getting hung on ODBC connections. I am guessing and hoping that the Witango client keeps serving requests to all available Witango services. I believe Robert had the solution to take care of this by having the Witango client and IIS loaded on a second server and using DNS load balancing. Like he mentioned, this would work for MOST of the requests. If you used the hardware DNS load balancing solution to stop requests from going to the failed IIS and Witango client server, it should probably work "ALL" the time. As I understand round robin DNS would still route some of the requests to the failed server. Eventually I plan on having IIS and the Witango client loaded on both servers and using some form of DNS load balancing. Hope I'm correct in the info I'm writing to you. Someone please correct me if I'm wrong. Thanks Steve -----Original Message----- From: MC Tay [mailto:[EMAIL PROTECTED] Sent: Monday, October 08, 2007 12:20 AM To: [email protected] Subject: RE: Witango-Talk: Load Balancing Test Steve: In your configuration, what would happen if the server with the Witango client die or has hardware failure? Will the other server take over? MC At 04:02 PM 10/7/2007, you wrote: >Thanks Robert. This helps a lot. I had to use a different user for the >Witango service to get the ODBC connector for R:Base to work with dbs >located on a different server. Your further instructions ties it all >together and everything is working great. > >The more I get into load balancing the more excited I get. I didn't realize >that the Witango client operates independently of the Witango server. I did >some testing by killing the Witango service on the server that has IIS, >Witango client and Witango server running on it and everything still kept >chugging away. The Witango Client kept distributing jobs to the other server >and jobs that were already on the other server kept running fine. > >Even jobs that were running on the Witango client server where the Witango >service was killed were rerouted to the other server. Of course they lost >their user variables, but at least the user wasn't stuck. > >Now when I have time, I will have to work on a way to notify the user that >their session was interrupted and to log back in. > >Steve Fogelson > >-----Original Message----- >From: Robert Garcia [mailto:[EMAIL PROTECTED] >Sent: Saturday, October 06, 2007 6:20 PM >To: [email protected] >Subject: Re: Witango-Talk: Load Balancing Test > >You only need to SET this in IIS. However. Lets say that the IIS >server gets a request for domain ABC, file /about/index.tml. Now the >home directory for this IIS domain is \\server1\mysites\abc\. > >Now the iis passes this request to the witango plugin, which picks a >server from the load balancing pool. Now lets say that the server it >sends this request to is on a different machine, we will call it >witango1. > >When the request comes to witango1, witango one must also be able to >see the file /about/index.tml in the path of \\server1\mysites\abc\ >OR \\server1\mysites\abc\about\index.tml > >Also very important. Make a user on ALL of these machines, that has >FULL access to the paths you serve. So lets say that you make the >user WITANGO. Then make sure in IIS you set the home directory, and >the user to connect with as WITANGO. And then, ALSO make sure that >you go to the SERVICES panel, and alter the properties of the >witango55 service. Set it to login as Witango, and same pass. This >will make sure that all of your witango processes, and the IIS >process have EQUAL FULL rights to these served directories. This is >VERY important. > >One more tip. If you are going to run any external processes, like >executable files, do not run them from the network share. Witango has >a habit of crashing under load in this situation. On each WITANGO >server, make a directory, called c:\scripts and put any executables >in there on ALL WITANGO machines. This way you can run from code with >the same path of: > >c:\scripts\myscript.exe on any server, and this will help get around >this weakness of witango. > >-- > >Robert Garcia >President - BigHead Technology >VP Application Development - eventpix.com >13653 West Park Dr >Magalia, Ca 95954 >ph: 530.645.4040 x222 fax: 530.645.4040 >[EMAIL PROTECTED] - [EMAIL PROTECTED] >http://bighead.net/ - http://eventpix.com/ > >On Oct 6, 2007, at 8:35 AM, Fogelson, Steve wrote: > > > Robert, > > > > Thanks for the great explanations. > > > > When you set the home directory in IIS to a share like > > \\server1\webfiles\mysite, I see that this would satisfy the IIS > > requirement > > in your statement "Each of the processes, the IIS process, and each > > Witango > > Server process must all see the same files with the same path". > > > > Does this share designation in IIS also satisfy the "Each of the > > processes > > and each Witango Server process"? Or is there somewhere else I need > > to do > > this? It seems like proper permissions and the Witango Client takes > > care of > > this automatically. > > > > Steve > > > > -----Original Message----- > > From: Robert Garcia [mailto:[EMAIL PROTECTED] > > Sent: Friday, October 05, 2007 6:06 PM > > To: [email protected] > > Subject: Re: Witango-Talk: Load Balancing Test > > > > Its ok. > > > > If you ONLY have 1 IIS server, then you are NOT doing DNS load > > balancing. If your IIS server is at IP 10.0.1.1, then your domain > > points to it, (www.mysite.com 10.0.1.1) then the is no dns load > > balancing. When the request comes into your IIS server, the witango > > plugin looks at the clients.ini file, and will load balance the > > requests across however many of witango servers you have. Each of the > > processes, the IIS process, and each Witango Server process must all > > see the same files with the same path. > > > > DNS load balancing occurs when you have more than one IIS server for > > the same domain. You can have any number of IIS servers connecting to > > any number of witango servers. The IIS server may or may not be on > > the same server as the IIS servers. > > > > When you have say 4 IIS servers, for the same domain, then there are > > a couple of ways to load balance. The first is with a hardware load > > balancer, which is expensive, but provides better switching upon the > > failure of a web server. > > > > The easy method is called round robin load balancing. All it requires > > is that you enter multiple A records in your dns server for the same > > domain. > > > > www.mysite.com A 10.0.1.1 > > www.mysite.com A 10.0.1.2 > > www.mysite.com A 10.0.1.3 > > www.mysite.com A 10.0.1.4 > > > > When the browser requests address for www.mysite.com it will get all > > of these, or randomly one. If it gets all, it will only try one. Load > > balancing this way works fairly well, but shows its weakness when a > > single IIS server dies. The you must alter your DNS to remove the > > entry of the faulty server. This is why it is best to enter a small > > TTL value for these multiple A records, like 30 minutes or so. > > > > -- > > > > Robert Garcia > > President - BigHead Technology > > VP Application Development - eventpix.com > > 13653 West Park Dr > > Magalia, Ca 95954 > > ph: 530.645.4040 x222 fax: 530.645.4040 > > [EMAIL PROTECTED] - [EMAIL PROTECTED] > > http://bighead.net/ - http://eventpix.com/ > > > > On Oct 5, 2007, at 3:07 PM, Fogelson, Steve wrote: > > > >> Robert, > >> > >> I don't mean to question, but I would like to understand. > >> > >> I don't have IIS running on the second server. I don't understand > >> DNS load > >> balancing, but are you running all of your Witango websites on both > >> of the > >> servers that you are running IIS and the Witango Client and then > >> using DNS > >> Load Balancing to spread the requests across both servers? > >> > >> If so, it makes sense to have the UNC notation you have indicated > >> below so > >> you only have to place all the files in one location. > >> > >> Thanks, > >> > >> Steve > >> > >> -----Original Message----- > >> From: Robert Garcia [mailto:[EMAIL PROTECTED] > >> Sent: Friday, October 05, 2007 4:46 PM > >> To: [email protected] > >> Subject: Re: Witango-Talk: Load Balancing Test > >> > >> In IIS, you set the home directory as a share on another computer. > >> You set the path using UNC notation, like \\server1\webfiles\mysite > >> or whatever. This path must point to same files for the IIS server, > >> and all witango services. I have a setup with 7 servers for instance. > >> 2 IIS servers with witango plugins, and 6 witango servers and one > >> file server they can all see with same UNC path. > >> > >> When IIS gets a request, it passes it on to witango service with > >> path, and the witango service pulls the file and processes. > >> > >> -- > >> > >> Robert Garcia > >> President - BigHead Technology > >> VP Application Development - eventpix.com > >> 13653 West Park Dr > >> Magalia, Ca 95954 > >> ph: 530.645.4040 x222 fax: 530.645.4040 > >> [EMAIL PROTECTED] - [EMAIL PROTECTED] > >> http://bighead.net/ - http://eventpix.com/ > >> > >> On Oct 5, 2007, at 2:34 PM, Fogelson, Steve wrote: > >> > >>> Robert, > >>> > >>> Where in Windows, IIS or Witango do you indicate or use this? My > >>> setup is > >>> working correctly without this. > >>> > >>> Unless: > >>> Maybe because I have shares setup on each server with > >>> Administrative Rights > >>> as follows: > >>> \\ics9\wwwroot > >>> \\ics14\wwwroot > >>> > >>> Thanks, > >>> > >>> Steve > >>> > >>> -----Original Message----- > >>> From: Robert Garcia [mailto:[EMAIL PROTECTED] > >>> Sent: Friday, October 05, 2007 4:04 PM > >>> To: [email protected] > >>> Subject: Re: Witango-Talk: Load Balancing Test > >>> > >>> Both servers need to have access to the files, and the web > >>> directory, > >>> and the path to the files must be the same for both servers. LIke: > >>> > >>> \\Server1\webfiles\mysite\ > >>> > >>> -- > >>> > >>> Robert Garcia > >>> President - BigHead Technology > >>> VP Application Development - eventpix.com > >>> 13653 West Park Dr > >>> Magalia, Ca 95954 > >>> ph: 530.645.4040 x222 fax: 530.645.4040 > >>> [EMAIL PROTECTED] - [EMAIL PROTECTED] > >>> http://bighead.net/ - http://eventpix.com/ > >>> > >>> On Oct 5, 2007, at 1:53 PM, Fogelson, Steve wrote: > >>> > >>>> Hi, > >>>> > >>>> I ran a test with the following setup. > >>>> > >>>> Server A will run one Witango service and the databases will reside > >>>> here. > >>>> Server B will run IIS, Witango Client and one Witango service > >>>> > >>>> Server B contains all the Witango and web files in the wwwroot > >>>> folder. IIS > >>>> is setup to run this website. > >>>> > >>>> Server A does not contain any Witango and web files for this > >>>> application. > >>>> IIS is not setup to run this web site. > >>>> > >>>> DNS points to the IIS website running on Server B. > >>>> > >>>> The apps runs fine repeatedly (closing the browser and opening a > >>>> new one). I > >>>> can tell which Witango Service is serving the browser because one > >>>> of my > >>>> Witango services is running on a 30 day trial license and the green > >>>> trailer > >>>> displays when the browser is using this service. Also the Witango > >>>> log files > >>>> on both servers show evidence of the app running on them. > >>>> > >>>> I am concluding that the Witango apps and html files only have to > >>>> be placed > >>>> on the server hosting the IIS service and Witango Client. In this > >>>> test, > >>>> server B. It appears that server A reads the Witango files from > >>>> server B and > >>>> caches them for further use. > >>>> > >>>> So it also appears that you only have to maintain one set of files > >>>> on the > >>>> IIS and Witango Client server. You don't need them on subsequent > >>>> Witango > >>>> servers included in the load balancing farm. > >>>> > >>>> Comments would be appreciated. Maybe everyone knows this and I just > >>>> didn't > >>>> get it. > >>>> > >>>> Thanks > >>>> > >>>> Steve Fogelson > >>>> Internet Commerce Solutions > >>>> > >>>> FYI: Witango config for each server included below > >>>> > >>>> Server A > >>>> witango.ini > >>>> VALIDHOSTS=127.0.0.1:10.10.20.14 > >>>> > >>>> client.ini > >>>> [witango55_iis.dll] > >>>> WITANGO_SERVER=127.0.0.1,18155 > >>>> > >>>> Server B > >>>> witango.ini > >>>> VALIDHOSTS=127.0.0.1 > >>>> > >>>> client.ini > >>>> WITANGO_SERVER=XXX14,127.0.0.1,18155:XXX9,10.10.20.9,18155 > >>>> CONNECTION_TIMEOUT=0 > >>>> FORCE_SERVER_ARG_NAME=_SrvID > >>>> ___________________________________________________________________ > >>>> _ > >>>> _ > >>>> _ > >>>> __ > >>>> TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf > >>>> > >>> ____________________________________________________________________ > >>> _ > >>> _ > >>> __ > >>> TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf > >>> ____________________________________________________________________ > >>> _ > >>> _ > >>> __ > >>> TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf > >>> > >> _____________________________________________________________________ > >> _ > >> __ > >> TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf > >> _____________________________________________________________________ > >> _ > >> __ > >> TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf > >> > > ______________________________________________________________________ > > __ > > TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf > > ______________________________________________________________________ > > __ > > TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf > > >________________________________________________________________________ >TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf >________________________________________________________________________ >TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf ________________________________________________________________________ TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf ________________________________________________________________________ TO UNSUBSCRIBE: Go to http://www.witango.com/developer/maillist.taf
