Comments on: Sticky load balance with Apache HTTPD 2.2 http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/ Consulting/Development in Java, Objective-C for web based systems and iPhone Wed, 14 Jul 2010 20:54:16 +0200 http://wordpress.org/?v=2.9.2 hourly 1 By: admin http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-2772 admin Tue, 05 Jan 2010 15:34:47 +0000 http://www.jakeri.net/?p=62#comment-2772 Ah, they have added an example to the Apache 2.3 documentation. Nice! Ah, they have added an example to the Apache 2.3 documentation. Nice!

]]> By: Ramesh M http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-2763 Ramesh M Tue, 05 Jan 2010 09:33:59 +0000 http://www.jakeri.net/?p=62#comment-2763 Sorry, I missed out the link, here it is. Actually this is apache 2.3 http://httpd.apache.org/docs/2.3/mod/mod_proxy_balancer.html Regards, Ramesh M Sorry, I missed out the link, here it is. Actually this is apache 2.3

http://httpd.apache.org/docs/2.3/mod/mod_proxy_balancer.html

Regards,
Ramesh M

]]> By: Ramesh M http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-2760 Ramesh M Tue, 05 Jan 2010 06:32:47 +0000 http://www.jakeri.net/?p=62#comment-2760 Would this be of any help for the syntax? Thanks, Ramesh M Would this be of any help for the syntax?
Thanks,
Ramesh M

]]> By: alopez http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-2354 alopez Wed, 09 Dec 2009 21:51:07 +0000 http://www.jakeri.net/?p=62#comment-2354 Can you easily make Cookies created on from the apache load balancer expire, say 5 minutes into the future? mod_rewrite appears to create Cookies that can expire in 5 minutes but can it utilize the environment variables you are using, e.g. BALANCER_WORKER_ROUTE? There are times where Cookies with a short life span can be advantageous. Can you easily make Cookies created on from the apache load balancer expire, say 5 minutes into the future?
mod_rewrite appears to create Cookies that can expire in 5 minutes but can it utilize the environment variables you are using, e.g. BALANCER_WORKER_ROUTE?
There are times where Cookies with a short life span can be advantageous.

]]> By: admin http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-1898 admin Fri, 06 Nov 2009 09:54:16 +0000 http://www.jakeri.net/?p=62#comment-1898 Hi Igor, If a backend server is down Apache proxy balancer will set BALANCER_ROUTE_CHANGED to a new server and the user will get a new BALANCEID-cookie. /Jakob Hi Igor,

If a backend server is down Apache proxy balancer will set BALANCER_ROUTE_CHANGED to a new server and the user will get a new BALANCEID-cookie.

/Jakob

]]> By: igor http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-1896 igor Fri, 06 Nov 2009 01:26:07 +0000 http://www.jakeri.net/?p=62#comment-1896 Nice but I have one question: what will happen with the sticky sessions in case of backend server failure? Let's say the apache receives a request with a cookie for server1 but the server1 is down? Will it continue sending the requests to the dead server because of the sticky session? Thanks, Igor Nice but I have one question: what will happen with the sticky sessions in case of backend server failure? Let’s say the apache receives a request with a cookie for server1 but the server1 is down? Will it continue sending the requests to the dead server because of the sticky session?

Thanks,
Igor

]]> By: admin http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-662 admin Thu, 23 Jul 2009 06:54:26 +0000 http://www.jakeri.net/?p=62#comment-662 No at all. Spread the word and keep a link to the original post. No at all.
Spread the word and keep a link to the original post.

]]> By: joao cosme jr http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-658 joao cosme jr Wed, 22 Jul 2009 17:19:57 +0000 http://www.jakeri.net/?p=62#comment-658 Simple GREAT!!! would you mind if i translate your post to PT_BR?? Simple GREAT!!!
would you mind if i translate your post to PT_BR??

]]> By: admin http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-303 admin Fri, 20 Mar 2009 22:10:27 +0000 http://www.jakeri.net/?p=62#comment-303 No. I don't think so. I believe you are referring to the "hej."-part. Take a look at mod_proxy (http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxypass) documentation and you will see that the route-directive is "Route of the worker when used inside load balancer. The route is a value appended to session id.". Take for instance a JSESSIONID-cookie for a tomcat. It usually look something like this JSESSIONID=42345234jfrfj4343.instance1, where the first part is the actual sessionid and the second part is the jvmroute set in server.xml. If you would use a tomcat you could just update the jvmroute in server.xml (in this example to server1, server2 and server3) for your servers and then change stickysession to JSESSIONID. No set header part needed at all. But sometimes you do not have good routing field set for each server or you are just lazy and want the proxy handle it. The httpd will elect one server based on the loadbalancing algorithm (default is byrequest) and set this value to the BALANCER_WORKER_ROUTE environment variable. If there is no cookie set (or a failure occurs) BALANCER_ROUTE_CHANGED will be 1 and write header SetCookie BALANCEID=hej.server1; path=/;. Next time when the same user arrives BALANCEID cookie is set and routed to server1. I hope my explanation was understandable. :-) Jakob No. I don’t think so.

I believe you are referring to the “hej.”-part. Take a look at mod_proxy (http://httpd.apache.org/docs/2.2/mod/mod_proxy.html#proxypass) documentation and you will see that the route-directive is “Route of the worker when used inside load balancer. The route is a value appended to session id.”.

Take for instance a JSESSIONID-cookie for a tomcat. It usually look something like this JSESSIONID=42345234jfrfj4343.instance1, where the first part is the actual sessionid and the second part is the jvmroute set in server.xml.
If you would use a tomcat you could just update the jvmroute in server.xml (in this example to server1, server2 and server3) for your servers and then change stickysession to JSESSIONID. No set header part needed at all.

But sometimes you do not have good routing field set for each server or you are just lazy and want the proxy handle it.
The httpd will elect one server based on the loadbalancing algorithm (default is byrequest) and set this value to the BALANCER_WORKER_ROUTE environment variable. If there is no cookie set (or a failure occurs) BALANCER_ROUTE_CHANGED will be 1 and write header SetCookie BALANCEID=hej.server1; path=/;. Next time when the same user arrives BALANCEID cookie is set and routed to server1.

I hope my explanation was understandable. :-)

Jakob

]]> By: Mark http://www.jakeri.net/2009/03/sticky-load-balance-with-apache-httpd-22/comment-page-1/#comment-302 Mark Fri, 20 Mar 2009 19:42:52 +0000 http://www.jakeri.net/?p=62#comment-302 Is there a typo in your post? You are setting the value for the cookie to: BALANCEID=hej.%{BALANCER_WORKER_ROUTE}e But your routes are specified as: route=server1 route=server2 route=server3 And your stickiness is specified as the value of the cookie which won't match the route values: stickysession=BALANCEID Mark Is there a typo in your post? You are setting the value for the cookie to:

BALANCEID=hej.%{BALANCER_WORKER_ROUTE}e

But your routes are specified as:

route=server1
route=server2
route=server3

And your stickiness is specified as the value of the cookie which won’t match the route values:

stickysession=BALANCEID

Mark

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