Hiding jsessionid parameter from Google using apache

If you're running a website on JBoss you may discover that Google has indexed your pages with a jsessionid query parameter in the links.

The Google crawl bot does not support cookies, therefore JBoss uses the jsessionid query parameter in order to maintain a session state without cookies. These query parameters can impact your Google rank and indexing efficiency as the same page can be indexed multiple times with different session ids, and dilute your ranking. Also, it leads to ugly links.

If you want to still be able to support non-cookie using users, but would like Google to see cleaner links, you can use Apache's mod_rewrite to modify the links for the Google bot only, leaving the normal functionality available to the rest of your users.

Assuming you have mod_rewrite enabled in your Apache instance, use this configuration in your apache config:

 # This should strip out jsessionids from google
 RewriteCond %{HTTP_USER_AGENT} (googlebot) [NC]
 ReWriteRule ^(.*);jsessionid=[A-Za-z0-9]+(.*)$ $1$2 [L,R=301]

This rule says for request where the user agent contains "googlebot" (with case insensitive matching), rewrite the URL without the jsessionid. It seems to work nicely.

jk_lb_worker.c All tomcat instances failed, no more workers left for recovery

We are getting a issue on our site getting down with following message in mod_jk.log

[Tue Sep 03 16:22:34 2013][22149:1585183040] [info] service::jk_lb_worker.c (1448): All tomcat instances failed, no more workers left for recovery (attempt=0, retry=0)

[Tue Sep 03 16:22:34 2013][22149:1585183040] [info] service::jk_lb_worker.c (1457): All tomcat instances failed, no more workers left (attempt=1, retry=0)
[Tue Sep 03 16:22:34 2013][22149:1501264192] [info] service::jk_lb_worker.c (1448): All tomcat instances failed, no more workers left for recovery (attempt=0, retry=0)
[Tue Sep 03 16:22:34 2013][22149:1501264192] [info] service::jk_lb_worker.c (1457): All tomcat instances failed, no more workers left (attempt=1, retry=0)
[Tue Sep 03 16:22:34 2013][22149:1616652608] [info] service::jk_lb_worker.c (1457): All tomcat instances failed, no more workers left (attempt=0, retry=1)
[Tue Sep 03 16:22:34 2013][22149:1616652608] [info] service::jk_lb_worker.c (1457): All tomcat instances failed, no more workers left (attempt=1, retry=1)
[Tue Sep 03 16:22:34 2013][22149:1616652608] [info] service::jk_lb_worker.c (1468): All tomcat instances are busy or in error state
[Tue Sep 03 16:22:34 2013][22149:1616652608] [error] service::jk_lb_worker.c (1473): All tomcat instances failed, no more workers left
[Tue Sep 03 16:22:34 2013]loadbalancer - naf.timesjobs.com 0 0.100549 POST /naf/log.html 200
[Tue Sep 03 16:22:34 2013][22149:1616652608] [info] jk_handler::mod_jk.c (2627): Service error=0 for worker=loadbalancer
[Tue Sep 03 16:22:34 2013][22149:1606162752] [info] service::jk_lb_worker.c (1457): All tomcat instances failed, no more workers left (attempt=0, retry=1)
[Tue Sep 03 16:22:34 2013][22149:1606162752] [info] service::jk_lb_worker.c (1457): All tomcat instances failed, no more workers left (attempt=1, retry=1)
[Tue Sep 03 16:22:34 2013][22149:1606162752] [info] service::jk_lb_worker.c (1468): All tomcat instances are busy or in error state
[Tue Sep 03 16:22:34 2013][22149:1606162752] [error] service::jk_lb_worker.c (1473): All tomcat instances failed, no more workers left
[Tue Sep 03 16:22:34 2013]loadbalancer - naf.timesjobs.com 0 0.100469 POST /naf/log.html 200
[Tue Sep 03 16:22:34 2013][22149:1606162752] [info] jk_handler::mod_jk.c (2627): Service error=0 for worker=loadbalancer
[Tue Sep 03 16:22:34 2013][22149:1690081600] [info] service::jk_lb_worker.c (1448): All tomcat instances failed, no more workers left for recovery (attempt=0, retry=0)
[Tue Sep 03 16:22:34 2013][22149:1690081600] [info] service::jk_lb_worker.c (1457): All tomcat instances failed, no more workers left (attempt=1, retry=0) 

mod-jk.conf

<IfModule mpm_worker_module>

    ThreadLimit         60

    ServerLimit         10

    StartServers        3

    MinSpareThreads     5

    MaxSpareThreads     20

    MaxClients          600

    ThreadsPerChild     60

    MaxRequestsPerChild 0

</IfModule>

While in tomcat server.xml   <Connector port="8009" protocol="AJP/1.3" redirectPort="8443" maxThreads="400" acceptCount="100"/>

Due to which the above error is coming at peak load when apache 600 request coming while tomcat is able to serve only 400.

We changed the setting  <Connector port="8009" protocol="AJP/1.3" redirectPort="8443" maxThreads="600" acceptCount="100"/>

and the problem got resolved.