Managing Serviceguard Seventeenth Edition, First Reprint December 2009

Creating Checkpoint and Snapshot Packages for CFS
The storage checkpoints and snapshots are two additional mount point package types.
They can be associated with the cluster via the cfsmntadm(1m) command.
Mount Point Packages for Storage Checkpoints
The Veritas File System provides a unique storage checkpoint facility which quickly
creates a persistent image of a filesystem at an exact point in time. Storage checkpoints
significantly reduce I/O overhead by identifying and maintaining only the filesystem
blocks that have changed since the last storage checkpoint or backup. This is done by
a copy-on-write technique. Unlike a disk-based mirroring technology, which requires
a separate storage space, this Veritas technology minimizes the use of disk space by
creating a storage checkpoint within the same free space available to the filesystem.
For more information about the technique, see the Veritas File System Administrator’s
Guide appropriate to your version of CFS, posted at http://docs.hp.com.
The following example illustrates how to create a storage checkpoint of the /cfs/mnt2
filesystem.
Start with a cluster-mounted file system.
1. Create a checkpoint of /tmp/logdata/log_files named check2. It is
recommended that the file system already be part of a mount point package that
is mounted.
cfsmntadm display
Cluster Configuration for Node: ftsys9
MOUNT POINT TYPE SHARED VOLUME DISK GROUP STATUS
/tmp/logdata/log_files regular log_files logdata MOUNTED
Cluster Configuration for Node: ftsys10
MOUNT POINT TYPE SHARED VOLUME DISK GROUP STATUS
/tmp/logdata/log_files regular log_files logdata MOUNTED
fsckptadm -n create check2 /tmp/logdata/log_files
2. Associate it with the cluster and mount it.
cfsmntadm add ckpt check2 /tmp/logdata/log_files \
/tmp/check_logfiles all=rw
Package name "SG-CFS-CK-2" was generated to control the resource
Mount point "/tmp/check_logfiles" was associated to the cluster
cfsmount /tmp/check_logfiles
3. Verify:
cmviewcl
CLUSTER STATUS
cfs-cluster up
NODE STATUS STATE
ftsys9 up running
242 Building an HA Cluster Configuration