Configuring One Adoptive Node to Support Failover of Multiple Packages

This configuration has two packages, each owned by a different server. The adoptive node for both packages is the same host. This sample configuration uses the package control option, which prevents the adoptive node from adopting another package if it has already adopted one. Figure 3-3 “One Adoptive Node for Two Packages” illustrates this configuration. Figure 3-4 “One Adoptive Node for Two Packages After One Server Fails” shows the same configuration after one primary server has failed.

Figure 3-3 One Adoptive Node for Two Packages

Figure 3-4 “One Adoptive Node for Two Packages After One Server Fails” shows this sample configuration after host basil has failed. Host sage has adopted pkg02.




	NOTE: Setting the package control option (`-d`) of the cmmodpkg command, prevents host `sage` from adopting another package, so host `sage` is no longer an adoptive node for `pkg01`. This prevent the adoptive node (`sage`) from becomming overloaded when multiple packages failover.

Figure 3-4 One Adoptive Node for Two Packages After One Server Fails

Cluster Configuration File for Adoptive Node for Two Packages

This section shows the cluster configuration file (cluster.conf) for this configuration example. The comments are not shown.

CLUSTER_NAME                      PkgCtrl
 
QS_HOST                           qs
QS_POLLING_INTERVAL               300000000
 
NODE_NAME                         thyme
  NETWORK_INTERFACE               eth0
    HEARTBEAT_IP                  192.100.112.146
  NETWORK_INTERFACE               eth1
 
NODE_NAME                         basil
  NETWORK_INTERFACE               eth0
    HEARTBEAT_IP                  192.100.112.168
 
NODE_NAME                         sage
  NETWORK_INTERFACE               eth0
    HEARTBEAT_IP                  192.100.112.184
  NETWORK_INTERFACE               eth1
  NETWORK_INTERFACE               eth2
 
HEARTBEAT_INTERVAL                1000000
NODE_TIMEOUT                      5000000
 
AUTO_START_TIMEOUT                600000000
NETWORK_POLLING_INTERVAL          2000000
 
MAX_CONFIGURED_PACKAGES           4

Package Configuration File for pkg01

This section shows the package configuration file (pkg1.conf) for the package pkg01 in this sample configuration. The comments are not shown.

PACKAGE_NAME               pkg01
PACKAGE_TYPE               FAILOVER
FAILOVER_POLICY            CONFIGURED_NODE
FAILBACK_POLICY            MANUAL
NODE_NAME                  thyme
NODE_NAME                  sage
AUTO_RUN                   YES
NODE_FAIL_FAST_ENABLED     NO
RUN_SCRIPT                 /usr/local/cmcluster/pkg1/pkg1.conf
RUN_SCRIPT_TIMEOUT         NO_TIMEOUT
HALT_SCRIPT                /usr/local/cmcluster/pgk1/pkg1.conf
HALT_SCRIPT_TIMEOUT        NO_TIMEOUT
SERVICE_NAME               nfs1.monitor
SERVICE_FAIL_FAST_ENABLED  NO
SERVICE_HALT_TIMEOUT       300
SUBNET                     192.100.112.0

Package Control Script for pkg01

This section shows the package control script (pkg1.cntl) for the package pkg01 in this sample configuration. Only the user-configured part of the script is shown; the executable part of the script and most of the comments have been omitted.

PATH=/sbin:/usr/bin:/usr/sbin:/etc:/bin:usr/local/
cmcluster/bin
RAIDTAB="/usr/local/cmcluster/conf/raidtab.sg"   
RAIDSTART="raidstart -c ${RAIDTAB}"
RAIDSTOP="raidstop -c ${RAIDTAB}"
VGCHANGE="vgchange -a y"                # Default
VG[0]="nfsu01"
MD[0]="/dev/md0"
LV[0]=/dev/nfsu01/lvol1; 
FS[0]=/hanfs/nfsu011; 
FS_TYPE[0]="ext2"; 
FS_MOUNT_OPT[0]="-o rw"
# FS_UMOUNT_COUNT=""
# FS_MOUNT_RETRY_COUNT=""
IP[0]="192.100.112.243"
SUBNET[0]="192.100.112.0"
HA_APP_SERVER="pre-IP"
#SERVICE_NAME[0]=""
#SERVICE_CMD[0]=""
#SERVICE_RESTART[0]=""

The function customer_defined_run_cmds calls the cmmodpkg command with the package control option (-d). This command prevents the host that is running pkg01 from adopting pkg02. The ampersand (&) causes the cmmodpkg command to run in the background. It must run in the background to allow the control script to complete.

There is a short time, after one primary node has failed but before the cmmodpkg command has executed, when the other primary node can fail and the adoptive node will adopt its package. In other words, if both thyme and basil fail at approximately the same time, host sage may adopt two packages, even though the package control option is specified.

If you omit the cmmodpkg -d command from the NFS control script, host sage can adopt both pkg01 and pkg02 if their primary nodes fail.

NFS Control Script for pkg01

This section shows the NFS control script (hanfs.sh) for the package pkg03 on this sample configuration on the the user-configured part of the script is shown:

XFS[0]="-o rw *:/hanfs/nfsu011"
NFS_SERVICE_NAME[0]="nfs1.monitor"
NFS_SERVICE_CMD[0]="/usr/local/cmcluster/pkg1/nfs.mon"
NFS_SERVICE_RESTART[0]="-r 0"

Package Configuration File for pkg02

This section shows the package configuration file (pkg2.conf) for the package pkg02 in this sample configuration. The comments are not shown.

PACKAGE_NAME               pkg02
PACKAGE_TYPE               FAILOVER
FAILOVER_POLICY            CONFIGURED_NODE
FAILBACK_POLICY            MANUAL
NODE_NAME                  basil
NODE_NAME                  sage
AUTO_RUN                   YES
NODE_FAIL_FAST_ENABLED     NO
RUN_SCRIPT                 /usr/local/cmcluster/pkg2/pkg2.conf
RUN_SCRIPT_TIMEOUT         NO_TIMEOUT
HALT_SCRIPT                /usr/local/cmcluster/pgk2/pkg2.conf
HALT_SCRIPT_TIMEOUT        NO_TIMEOUT
SERVICE_NAME               nfs2.monitor
SERVICE_FAIL_FAST_ENABLED  NO
SERVICE_HALT_TIMEOUT       300
SUBNET                     192.100.112.0

Package Control Script for pkg02

This section shows the package control script (pkg2.cntl) for the package pkg02 in this sample configuration. Only the user-configured part of the script is shown; the executable part of the script and most of the comments have been omitted.

PATH=/sbin:/usr/bin:/usr/sbin:/etc:/bin:usr/local/
cmcluster/bin
RAIDTAB="/usr/local/cmcluster/conf/raidtab.sg"   
RAIDSTART="raidstart -c ${RAIDTAB}"
RAIDSTOP="raidstop -c ${RAIDTAB}"
VGCHANGE="vgchange -a y"                # Default
VG[0]="nfsu02"
MD[0]="/dev/md1"
LV[0]=/dev/nfsu02/lvol1; 
FS[0]=/hanfs/nfsu021; 
FS_TYPE[0]="ext2"; 
FS_MOUNT_OPT[0]="-o rw"
# FS_UMOUNT_COUNT=""
# FS_MOUNT_RETRY_COUNT=""
IP[0]="192.100.112.244"
SUBNET[0]="192.100.112.0"
HA_APP_SERVER="pre-IP"
#SERVICE_NAME[0]=""
#SERVICE_CMD[0]=""
#SERVICE_RESTART[0]=""

The function customer_defined_run_cmds calls the cmmodpkg command with the package control option (-d). This command prevents the host that is running pkg02 from adopting pkg01. The ampersand (&) causes the cmmodpkg command to run in the background. It must run in the background to allow the control script to complete.

If you omit the cmmodpkg -d command from the NFS control script, host sage can adopt both pkg01 and pkg02 if their primary nodes fail.

NFS Control Script for pkg02

This section shows the NFS control script (hanfs.sh) for the package pkg02 on this sample configuration on the the user-configured part of the script is shown:

XFS[0]="-o rw *:/hanfs/nfsu021"
NFS_SERVICE_NAME[0]="nfs2.monitor"
NFS_SERVICE_CMD[0]="/usr/local/cmcluster/pkg2/nfs.mon"
NFS_SERVICE_RESTART[0]="-r 0"