Ensure that you are familiar with the constraints for zoning
a switch to support the Metro Mirror and Global Mirror feature.
SAN configurations that use intrasystem Metro Mirror
and Global Mirror relationships do not require more switch zones.
You can zone Fibre Channel over Ethernet (FCoE) ports on
system 1 with Fibre Channel (FC) ports of system 2 or FCoE ports on system 1 with FCoE ports on
system 2 to support Metro Mirror and Global Mirror replications.
For
intersystem Metro Mirror and Global Mirror relationships, you must
complete the following steps to create the additional zones that are
required:
- Configure your SAN so that Fibre Channel traffic
can be passed between the two clustered systems.
To configure the SAN this way, you can connect the systems to the
same SAN, merge the SANs, or use routing technologies.
- Optional: Configure zoning to enable
the nodes in the local fabric to communicate with the nodes in the
remote fabric.
For Metro Mirror and Global Mirror configurations
where the round-trip latency between systems is less than 80 milliseconds,
zone two Fibre Channel ports on each node in the local system to two
Fibre Channel ports on each node in the remote system. If dual-redundant
fabrics are available, zone one port from each node across on each
fabric to provide the greatest fault tolerance. No other Fibre Channel
ports on any node should have remote zones.
If the round-trip latency between systems is greater than 80 milliseconds,
stricter configuration requirements apply:
- Use SAN zoning and port masking to ensure that two Fibre Channel ports on each node that is
used for replication are dedicated for replication traffic.
- Apply SAN zoning to provide separate intersystem zones for each local-to-remote I/O group
pair that is used for replication. See the information about long-distance links for Metro
Mirror and Global Mirror partnerships for further details.
- Optional: As an alternative to step #svc_zoningconsidforrc_2lsn1j/allnodes,
choose a subset of nodes in the local system to be zoned to the nodes in the remote system.
Minimally, you must ensure that one whole I/O group in the local system has connectivity to one
whole I/O group in the remote system. I/O between the nodes in each system is then routed to find a
path that is permitted by the configured zoning.
Reducing the number of nodes that are zoned
together can reduce the complexity of the intersystem zoning and might reduce the cost of the
routing hardware that is required for large installations. Reducing the number of nodes also means
that I/O must make extra hops between the nodes in the system, which increases the load on the
intermediate nodes and can increase the performance impact, especially for Metro Mirror configurations.
- Optional: Modify the zoning so that the hosts that are visible
to the local system can recognize the remote system. This zoning enables
a host to examine data in both the local and remote system.
- Verify that system A cannot recognize any of the back-end storage
that is owned by system B. A system cannot access logical units (LUs)
that a host or another system can also access.