Steps for setting up sysplex distributor to be the service manager for the Cisco MNLB (IPv4 only)

You can use a combination of the sysplex distributor and the Cisco MNLB to provide workload balancing.

Perform the following steps to set up sysplex distributor to be the service manager for the Cisco MNLB:

1. The Cisco router must be configured as a forwarding agent. The IP CASA control address (which is NOT the interface address to the forwarding agent) must be advertised by the Cisco routing daemons. This is not automatically done by Cisco and must be enabled by a Cisco command. For more information on the commands, see online documentation for Cisco at: http://www.cisco.com.
2. Specify the SERVICEMGR keyword on the VIPADEFine statement in the TCPIP profile.
3. Specify the VIPASMparms statement in the TCPIP profile. Specify the same multicast group and UDP port on the VIPASMparms statement in the TCPIP profile as are configured in the MNLB.
4. Optionally, use MD5 authentication: Specify the same password (MD5 key) on the VIPASMparms statement in the TCPIP profile as is configured on the Cisco routers which will communicate with the sysplex distributor. If a password (SMPASSword) is specified, then the sysplex distributor will perform MD5 authentication for all communications with the Cisco forwarding agents. For both the Cisco forwarding agent and the sysplex distributor, the password is treated as ASCII characters. No translation or conversion is performed. For more information on MD5 authentication, see RFC 1321.
5. If you are using V1R7 or later, configure all forwarding agents with IP PIM DENSE-MODE to ensure that MNLB packets are forwarded properly.
6. If using the Cisco MNLB in a configuration where there is an OSA adapter between a Cisco router and the destination TCP/IP stacks such that multiple stacks are sharing the OSA, configure Virtual MAC (VMAC) addressing on each of the destination TCP/IP stacks or configure GRE tunnels on the Cisco routers. The sysplex distributor stack is the only stack that registers the dynamic VIPA to OSA. Therefore, if VMACs or GRE tunnels are not configured, OSA will send all packets destined for the DVIPA to the sysplex distributor stack (or to the default router stack if the OSA is not shared with the sysplex distributor stack).

   When configuring GRE tunnels, you must configure them on the Cisco router such that any packets destined for a DVIPA that are routed by the forwarding agents directly to TCP/IP target stacks are encapsulated to the target stack's dynamic XCF address or, if specified in the distributor, to the VIPAROUTE target IP address. If the primary and backup TCP/IP stacks specify different VIPAROUTE statements for a particular target, you must define GRE tunnels for each target IP address that might be used.

   For more detailed information about configuring VMACs, see z/OS Communications Server: SNA Network Implementation Guide, or see OSA-Express virtual MAC routing. For more detailed information about configuring GRE tunnels, see the Cisco router publications located at http://www.cisco.com.

7. Special consideration must be made for each target stack that will receive data from an OSA that is not shared with the distributor stack. Connection load balanced IP packets routed to target stacks that do not use GRE tunnels will arrive with a destination address of the dynamic VIPA address. Only the OSA associated with the distributor stack is aware of the dynamic VIPA address. If the target stack is not the primary router for this OSA, or does not have Virtual MAC (VMAC) addressing configured for this OSA, the OSA will discard the IP packet. In this case, you must either configure VMAC addressing for the OSA, configure GRE tunnels on the Cisco router, or configure the target stack to be the primary router for the OSA. If configuring GRE tunnels on the Cisco router, ensure that any packets destined for a DVIPA that are routed by the forwarding agents directly to TCP/IP target stacks are encapsulated to the target stack's dynamic XCF address or, if specified in the distributor, to the VIPAROUTE target IP address.
8. Verification:

   The Netstat VIPADCFG/-F report may be used to verify the configuration. See z/OS Communications Server: IP System Administrator's Commands for more information on this command.

   Cisco's show ip casa commands may be used to display MNLB information. For more detailed information on these commands, see Cisco's online documentation at: http://www.cisco.com.

VIPADYNAMIC                                                         
   VIPADEFINE  MOVEABLE IMMED SERVICEMGR 255.255.255.0 197.11.221.1  
   VIPASMPARMS SMMCAST 224.0.1.2 SMPORT 1637 SMPASS ABCD
    VIPADIST 197.11.221.1 PORT 80 20 21 23                               
    DESTIP 199.11.87.104                                             
           199.11.87.105                                             
           199.11.87.106                                             
           199.11.87.108                                             
           199.11.87.109                                             
           199.11.87.110                                             
ENDVIPADYNAMIC