Verifying that the Advisor system is functioning correctly (optional)

View the MVS™ console of the Advisor and Agent systems after they are started to verify that the applications started correctly and are still running. If there are any failure messages, see the appropriate message description for the appropriate corrective action. View the syslogd files of the Advisor and Agent systems to see whether any error or warning messages were issued.

Use the following commands to verify that the Advisor system is functioning correctly:

• Verify that the Advisor is started and connected to the expected load balancers by issuing the Advisor's MODIFY procname,DISPLAY,LB command. Verify that each load balancer is displayed. Take note of the LB INDEX displayed for each load balancer. This identifier is needed to display details of the load balancer, including its registered groups and members.
  Tip: Individual load balancers are identified in displays by their load balancer index (LB Index), which is generated by the Advisor when the load balancer first connects. To display the details of a particular load balancer, first obtain the LB Index by displaying the list of all load balancers using the Advisor's MODIFY procname,DISPLAY,LB command. When you have the LB Index, display the details of a particular load balancer using the appropriate LB Index on the INDEX parameter as follows:

  MODIFY procname,DISPLAY,LB,INDEX=lb_index

• Verify that each load balancer configured and registered the appropriate groups and members with the Advisor by issuing the following command:

  MODIFY procname,DISPLAY,LB,INDEX=assigned_lb_index

  This display should show all groups and members defined to the load balancer.

• Verify that each Agent has started properly and is communicating with the Advisor. On each Agent, issue the following command:

  MODIFY procname,DISPLAY,MEMBERS

  Each member that has an IP address owned by this Agent should appear in the display.

• Verify that the target applications that you want to load balance to are actually available for load balancing. On the Advisor, for each load balancer connected to the Advisor, issue the following command:

  MODIFY procname,DISPLAY,LB,INDEX=assigned_lb_index

  Check for the AVAIL flag for each member in the display. The flag is either YES, meaning the member is available for load balancing, or NO, meaning it is not available for load balancing. To be available for load balancing, all of the following conditions must be true:

  • The Agent owning the member's IP address must be active and communicating with the Advisor.
  • The application must be active, if the member represents an application member, and must be on a TCP/IP stack that has not had eventual action message EZD1973E issued by sysplex problem detection and recovery. For more information, see Problem detection.
  • The member must not be quiesced by the Agent operator or the load balancer. The z/OS® Agent operator is able to quiesce any member that is owned by that Agent. Also, depending upon load balancer implementation, it might be possible for the load balancer administrator to quiesce individual members.

  If one of the above conditions is false, correct the situation and repeat the display command until you are satisfied that all members that you intend to have available for load balancing are displayed as being available.

• Verify that the Advisor system is functioning correctly when using AT-TLS:
  • Use the pasearch command from the z/OS UNIX shell to query information from the Policy Agent. For example, pasearch -t -r displays active AT-TLS rule details. For more information about displaying policy based networking information, see z/OS Communications Server: IP System Administrator's Commands.
  • Use the Netstat TTLS/-x command to display z/OS Load Balancing Advisor, Agent, and ADNR AT-TLS policies. For more information about the Netstat TTLS/-x report, see z/OS Communications Server: IP System Administrator's Commands.