Veritas Storage Foundation 5.1 SP1 Cluster File System Release Notes (5900-1509, April 2011)

■ IPv6 is not supported in a CVM and VVR cluster where some nodes in the
cluster are IPv4-only and other nodes in the same cluster are IPv6-only, or all
nodes of a cluster are IPv4-only and all nodes of a remote cluster are IPv6-only.
■ VVR does not support Edge and NAT-PT routers that facilitate IPv4 and IPv6
address translation.
VVR support for replicating across Storage Foundation versions
VVR supports replication between Storage Foundation 5.1SP1 and the prior major
releases of Storage Foundation (5.0 MP3 and 5.1). Replication between versions
is supported for disk group versions 140, 150, and 160 only. Both the Primary and
Secondary hosts must be using a supported disk group version.
Limitations related to I/O fencing
This section covers I/O fencing-related software limitations.
Stopping systems in clusters with I/O fencing configured
The I/O fencing feature protects against data corruption resulting from a failed
cluster interconnect, or “split brain.” See the Veritas Cluster Server Administrator's
Guide for a description of the problems a failed interconnect can create and the
protection I/O fencing provides.
I/O fencing uses SCSI-3 PR keys to implement data protection. Keys are placed
on I/O fencing coordinator points and on data disks. The VCS administrator must
be aware of several operational changes needed when working with clusters
protected by I/O fencing. Specific shutdown procedures ensure keys are removed
from coordinator points and data disks to prevent possible difficulties with
subsequent cluster startup.
Using the reboot command rather than the shutdown command bypasses shutdown
scripts and can leave keys on the coordinator points and data disks. Depending
on the order of reboot and subsequent startup events, the cluster may warn of a
possible split brain condition and fail to start up.
Workaround: Use the shutdown -r command on one node at a time and wait for
each node to complete shutdown.
Veritas Storage Foundation for Databases tools software limitations
The following are software limitations in this release of Veritas Volume Manager.
49Storage Foundation Cluster File System Release Notes
Software limitations