Data Assurance Considerations - Lenovo ThinkSystem DE Series Hardware Installation And Maintenance Manual

• If a storage array used for mirroring currently has only FC ports, and you want to convert some of them to
iSCSI, you must determine which ports are used for mirroring.
• You do not need to convert the ports on the local storage array and the remote storage array to the same
protocol as long as both storage arrays have at least one active FC port after the conversion.
• If you plan to convert the ports that are being used for mirrored relationships, you must deactivate any
synchronous or asynchronous mirror relationships before applying the feature pack. Synchronous
Mirroring is not supported for iSCSI.
• If you plan to convert the ports that are not being used for mirroring, asynchronous mirroring operations
will be unaffected.
• Before applying the feature pack, you should confirm that all mirror consistency groups are synchronized.
After applying the feature pack, you should test the communication between the local storage array and
the remote storage array.

Data Assurance considerations

• The Data Assurance (DA) feature is not supported for iSCSI. To ensure that data access remains
uninterrupted, you might need to remap or remove DA volumes from host clusters before applying the
feature pack.
If you have...
DA volumes in the default cluster
DA volumes in a host cluster that
contains FC-only hosts, and you
want to add iSCSI-only hosts
DA volumes in a host cluster that
contains FC-only hosts, or DA
volumes that are mapped to an
individual FC host partition
No partitions defined
You must...
Remap all the DA volumes in the default cluster.
– If you do not want to share DA volumes between hosts, follow these steps:
1. Create a host partition for each set of FC host ports (unless this has
already been done).
2. Remap the DA volumes to the appropriate host ports.
– If you want to share DA volumes between hosts, follow these steps:
1. Create a host partition for each set of FC host ports (unless this has
already been done).
2. Create a host cluster that includes the appropriate host ports.
3. Remap the DA volumes to the new host cluster.
Note: This approach eliminates volume access to any volumes that
remain in the default cluster.
Remove any DA volumes belonging to the cluster, using one of these options.
Note: DA volumes cannot be shared in this scenario.
– If you do not want to share DA volumes between hosts, remap all DA
volumes to individual FC hosts within the cluster.
– Segregate the iSCSI-only hosts into their own host cluster, and keep the
FC host cluster as is (with shared DA volumes).
– Add an FC HBA to the iSCSI-only hosts to allow for sharing of both DA and
non-DA volumes.
No action is needed before applying the feature pack. DA volumes will remain
mapped to their respective FC host.
No action is needed before applying the feature pack because no volumes are
currently mapped. After converting the host protocol, follow the proper
procedure to create host partitions and, if desired, host clusters.
.
Chapter 3 Hardware replacement procedures
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