Configuring Agents in a subplexing environment

When you are using subplexing, there can be more than one Agent per z/OS® system in the sysplex. In fact, there should be one Agent active for each subplex with a TCP/IP stack on a system that you want to participate in load balancing through the Load Balancing Advisor. Each Agent reads configuration data from a file, which can exist as a z/OS UNIX file, a PDS or PDSE member, or a sequential data set. In the configuration file for each Agent, the sysplex_group_name statement specifies the TCP/IP sysplex group name, in the form EZBTvvtt, where vv is the VTAM® subplex group ID specified with the VTAM XCFGRPID start option, and tt is the TCP/IP subplex group ID specified with the XCFGRPID parameter on the GLOBALCONFIG statement in the TCP/IP profile. If no VTAM subplex ID is specified when VTAM is started, then vv is CP. If no TCP/IP subplex ID is specified in the TCP/IP profile, then tt is CS. If you have a default subplex in your system (that is, a subplex in which both the VTAM and TCP/IP subplex IDs are not specified), configure the Load Balancing Agent for that subplex with a sysplex group name of EZBTCPCS.

Tip: In a subplexing environment, if you will have more than one Agent started on the same z/OS system (in different subplexes), create unique start procedures for them or ensure that they have unique job names when they are started (for example, S LBAGENT.AGE0105 or S LBAGENT,JOBNAME=AGE0105).
Requirements:
  • In a subplexing environment, the IP address used by the Agent to connect to the Advisor must exist on a TCP/IP stack belonging to the subplex that corresponds to the TCP/IP sysplex group name specified in the Agent's configuration file. If there is more than one TCP/IP stack in a subplex, the IP address must be a DVIPA defined within a VIPARANGE statement on each of the stacks in the subplex. This enables the Agent to connect regardless of the order that the TCP/IP stacks in the subplex are started.
  • If you have more than one stack on a system, those stacks are not all in the same subplex, and you will be starting Load Balancing Agents on that system, the system must not be at a level prior to V1R10.