Could someone comment on the potential timeline for supporting software raid in CLVM? Any hopes of it soon?
Does Red Hat Cluster Suite support software RAID (like Veritas and HP)?
by John Berninger
At the present time, software RAID drivers are not supported in the Red Hat Cluster Suite (RHCS) due to state maintenance issues between nodes.
The present versions of mdadm and RHCS are unable to transfer state information from one node to another in a cluster, so the node not actively using the file system is unable to determine the status of the RAID in case of a fence or STONITH operation. This inability could lead to file system corruption if a state is calculated incorrectly, which would likely be worse than not having the RAID in place in the beginning.
Red Hat engineers are working on a new volume manager, the Cluster Logical Volume Manager (CLVM), which will enable the use of LVM on shared storage. Once this work is complete, finalized testing and quality assurance will begin on making multi-pathed CLVM available for production use, which will act in place of software RAID in a cluster environment, providing similar functionality through different means.