Edge Load Balancer stops load balancing or forwarding packets
 Technote (troubleshooting)
 
Problem(Abstract)
This document shows what debugging information is needed if Edge Load Balancer stops load balancing or forwarding packets causing the clients to receive 404 errors and preventing them from hitting the cluster IP address.
 
Resolving the problem
The only fast solutions are to restart the load balancer or trigger a failover.
A dscontrol e stop run on the active load balancer is the simplest way to take the heartbeat down and cause a failover. If this is Microsoft® Windows®, the only option is to pull the network cable or reboot the system with the service set to Manual.


Debugging
If this is a High Availability (HA) setup, then run the xlog and packet trace on the active and "hung" load balancer systems.

While the load balancer box is "hung" or not load balancing, run the following commands:

dscontrol set loglevel 5
dscontrol e xloglevel 5

Depending on the operating system, start a packet trace on the load balancer:
  • For AIX®:
    iptrace -a -b iptrace.cap

  • For Linux®:
    tcpdump -w tcpdump.cap

  • For Solaris:
    snoop -o snoop.cap

  • For Microsoft Windows:
    Network Monitor trace on the interface, then save the trace to a file.

With the log levels set and the packet trace running, send in as few client requests as possible by running the following:

dscontrol e xlogtail 30000 >xlog.out
dscontrol e rep
dscontrol e stat
dscontrol cluster rep :
dscontrol cluster stat :
dscontrol e xm 1

Note: Some operating systems do not like the space between the "30000" and the ">".

Collect the following;
  1. xlog.out
  2. All dscontrol outputs
  3. Packet trace
  4. All logs from load balancer
  5. java -fullversion
  6. ifconfig -a
  7. netstat -nr
  8. netstat -ni
  9. arp -a
  10. netstat -an
  11. Depending on the operating system, collect the following:
    • For Linux: rpm -qa
    • For Solaris: pkginfo -l
    • For AIX: lslpp -l
    • For Microsoft Windows: Just need to know whether you are running Windows 2000 or 2003 and the fix pack level.

*Call into the 800-IBM-Serv and open a problem management record (PMR) with support to review the logs to determine the cause of the problem.
 
 
 


Document Information


Product categories: Software > Application Servers > Distributed Application & Web Servers > WebSphere Application Server > Edge Component
Operating system(s): Windows
Software version: Edge Server 2.0 GA
Software edition:
Reference #: 1177699
IBM Group: Software Group
Modified date: Aug 26, 2004