Designing Disaster Tolerant High Availability Clusters, 10th Edition, March 2003 (B7660-90013)

Building a Metropolitan Cluster Using MetroCluster/CA
Maintaining a Cluster that uses MetroCluster/CA
Chapter 3112
cluster operation, shows the percentage of the side file that is full:
# pairdisplay -g pkgB -fc -CLI
Group PairVol L/R Port# TID LU Seq# LDEV# P/S Status Fence
% P-LDEV# M
pkgB pkgD-disk0 L CL1-C 0 3 35422 463 P-VOL PAIR
ASYNC 35 3 -
pkgB pkgD-disk0 R CL1-F 0 3 35663 3 S-VOL PAIR
ASYNC 0 463 -
This output shows that 35% of the side file is full.
When volumes are in a COPY state, the % column shows the progress of
the copying between the XP frames, until it reaches 100%, at which point
the display reverts to showing the side file usage in the PAIR state.
Normal Maintenance
There might be situations when the package has to be taken down for
maintenance purposes without having the package move to another
node. The following procedure is recommended for normal maintenance
of the MetroCluster/CA:
1. Stop the package with the appropriate MC/ServiceGuard command.
# cmhaltpkg pkgname
2. Split links for the package.
# pairsplit -g <package device group name> -rw
3. Distribute the MetroCluster with Continuous Access XP
configuration changes.
# cmapplyconf -P pkgname.config
4. Start the package with the appropriate MC/ServiceGuard command:
# cmmodpkg -e pkgname
Planned maintenance is treated the same as a failure by the cluster. If
you take a node down for maintenance, package failover and quorum
calculation is based on the remaining nodes. Make sure that nodes are
taken down evenly at each site, and that enough nodes remain on-line to
form a quorum if a failure occurs. See “Example Failover Scenarios with
Two Arbitrators” on page 81.