These
are some of the limitations to a volume-based backup and restore:
- It is not granular, and does not provide individual file or volume restore
capability.
- You must save and restore all the volumes, including those containing
metadata and file data. The volumes in the system storage pool and the user
storage pools form a consistency group (that is, they must be backed up and
restored together).
- The SAN File System clients and the cluster must be quiesced
before performing a volume-based backup. In a fully-quiesced system, all file
system activity stops and all buffers are flushed to disk. Volume-based backups
are guaranteed to get a time-consistent view of the entire system in this
state. In a partially-quiesced system, all file system activity stops and
only the metadata buffers are flushed to disk. Volume-based backups are guaranteed
to get a time-consistent view of the metadata, but not file data because the
file buffers are not flushed to disk. Unless your applications can recover
from incomplete data writes, your system should be in the fully-quiesced state.