TMS zl Management and Configuration Guide ST.1.0.090213

1-63
Overview
HA Clusters
Multicast Routing
The TMS zl Module supports Internet Group Membership Protocol (IGMP),
which allows endpoints to join groups and receive traffic that is destined to
specific multicast addresses. You enable IGMP per-TMS VLAN.
The TMS zl Module also supports routing multicast traffic between TMS
VLANs. You must select the TMS VLANs on which multicast routing is enabled.
HA Clusters
Two TMS zl Modules can work together in an HA cluster, which provides high
availability and redundancy in the rare event of a module’s failure. The
modules in the HA cluster share connection state information. Should one
module fail, the other module assumes its active connections, and the system
is up and running again within several seconds.
HA is supported for modules that operate in routing mode. It is not supported
for monitor mode. If you require redundancy for monitor mode TMS zl Mod-
ules, simply mirror the same traffic to two modules.
HA Cluster Members
An HA cluster consists of two TMS zl Modules that operate in routing mode.
One member is the master, and the other is the participant.
After you activate HA on the two modules, the module configured with the
higher priority becomes the master. The participant synchronizes its configu-
ration with the master.
Note Make sure that the master is booted and configured for HA before you boot
the participant and activate HA on it. If the participant cannot contact the
master, it will assume the role of master. When the master eventually boots
and connects to the cluster, it will synchronize to the participant’s configura-
tion, causing the wrong configuration to be implemented.
The master manages the cluster, has an IP address on each TMS VLAN, and
receives all traffic for data processing. The participant stands by in case the
master fails. It has a virtual IP address on each TMS VLAN, which matches the
real IP address for those VLANs on the master.