Environment
NetIQ Access Manager 3.2
NetIQ Access Manager 3.2 Support Pack 2 applied
NetIQ Access Manager 3.2 Access Gateway (AG) protecting multiple back end applications
One AG application front ending 6 different back end servers with stickiness enabled
NetIQ Access Manager 3.2 Support Pack 2 applied
NetIQ Access Manager 3.2 Access Gateway (AG) protecting multiple back end applications
One AG application front ending 6 different back end servers with stickiness enabled
Situation
Access Manager 3.1 setup and working fine. After upgrading to Access Manager 3.2 SP2, users accessing one specific Peoplesoft application reported slowness and performance problems. The Access Gateway (AG) reverse proxy accelerating this Peoplesoft app was configured to load balance between 6 Peoplesoft web servers, with stickiness enabled.
On further investigation, the AG was sending requests to only 3 of the 6 Peoplesoft Web servers. The AG server-status application shows the load balancing statistics for the Balancer module, and this clearly showed that 3 of the servers had no requests eg.
Reverse Proxy Peoplesoft
SSes Timeout Method
ZNPCQ003-33333200 0 byrequests
Sch Host Stat Route Redir F Set Acc Wr Rd
http 23.14.93.156 Ok 39ef0f95 1 0 628 2.4M 1.7M
http 23.14.93.157 Ok ab1e37e9 1 0 0 0 0
http 23.14.93.158 Ok 0d26e398 1 0 585 2.1M 6.5M
http 23.14.93.159 Ok 37c6bba9 1 0 0 0 0
http 23.14.93.212 Ok 6faf9886 1 0 676 2.1M 1.5M
http 23.14.93.213 Ok 9cf93466 1 0 0 0 0
The issue does not re-appear when the server is rebooted.
On further investigation, the AG was sending requests to only 3 of the 6 Peoplesoft Web servers. The AG server-status application shows the load balancing statistics for the Balancer module, and this clearly showed that 3 of the servers had no requests eg.
Reverse Proxy Peoplesoft
SSes Timeout Method
ZNPCQ003-33333200 0 byrequests
Sch Host Stat Route Redir F Set Acc Wr Rd
http 23.14.93.156 Ok 39ef0f95 1 0 628 2.4M 1.7M
http 23.14.93.157 Ok ab1e37e9 1 0 0 0 0
http 23.14.93.158 Ok 0d26e398 1 0 585 2.1M 6.5M
http 23.14.93.159 Ok 37c6bba9 1 0 0 0 0
http 23.14.93.212 Ok 6faf9886 1 0 676 2.1M 1.5M
http 23.14.93.213 Ok 9cf93466 1 0 0 0 0
The issue does not re-appear when the server is rebooted.
Resolution
Perform the following changes on the AG:
The issue is triggered every time a change gets applied, whether the change is to the proxy having the issue (Peoplesoft) or another proxy on the system. By forcing the Apache to restart fully and not gracefully, we can work around the following Apache defect at https://issues.apache.org/bugzilla/show_bug.cgi?id=55152
a) open /opt/novell/nam/mag/webapps/agm/WEB-INF/agm.properties
b) search for the line 'linux.apache.command.gracefulrestart
= graceful'
c) replace it with 'linux.apache.command.gracefulrestart = restart'
The issue is triggered every time a change gets applied, whether the change is to the proxy having the issue (Peoplesoft) or another proxy on the system. By forcing the Apache to restart fully and not gracefully, we can work around the following Apache defect at https://issues.apache.org/bugzilla/show_bug.cgi?id=55152