Reconfiguring a Package

The process of reconfiguration of a package is somewhat like the basic configuration described in Chapter 6. Refer to that chapter for details on the configuration process.

The cluster can be either halted or running during package reconfiguration. The types of changes that can be made and the times when they take effect depend on whether the package is running or not.

Reconfiguring a Package on a Halted Cluster

You can also make permanent changes in package configuration while the cluster is not running. Use the following steps:

On one node, reconfigure the package as described earlier in this chapter. You can do this by using Serviceguard Manager or by editing the package ASCII file.
Edit the package control script directly if not in Serviceguard’s guided mode (in guided mode, Serviceguard manager does it automatically at reconfiguration). Any changes in service names will also require changes in the package configuration file.
Click the Apply button in Serviceguard Manager, or enter cmapplyconf on the command line. This copies the binary cluster configuration file to all nodes. On the command line, use the -P option, specifying the package to be changed; do not use the -C option. This file overwrites any previous version of the binary cluster configuration file.
Copy the modified control script to all nodes that can run the package. (Done automatically in Serviceguard Manager as part of Apply.)
Use the Serviceguard Manager Run Cluster command, or enter cmruncl on the command line to start the cluster on all nodes or on a subset of nodes, as desired. The package will start up as nodes come online.

Reconfiguring a Package on a Running Cluster

You can reconfigure a package while the cluster is running, and in some cases you can reconfigure the package while the package itself is running. Only certain changes may be made while the package is running.

To modify the package in Serviceguard Manager, select it and then choose Configuring Serviceguard from the Actions menu. When the configuration window opens, choose options as described in Chapter 6. Alternatively, with HP-UX commands, use the following procedure (pkg1 is used as an example):

Halt the package if necessary:
# cmhaltpkg pkg1
See Table 7-2 “Types of Changes to Packages ” to determine whether this step is needed.
If it is not already available, you can obtain a copy of the package's ASCII configuration file by using the cmgetconf command, specifying the package name.
# cmgetconf -p pkg1 pkg1.ascii
Edit the ASCII package configuration file.
Verify your changes as follows:
# cmcheckconf -v -P pkg1.ascii
Distribute your changes to all nodes:
# cmapplyconf -v -P pkg1.ascii
Copy the package control script to all nodes that can run the package.

Adding a Package to a Running Cluster

You can create a new package and add it to the cluster configuration while the cluster is up and while other packages are running. The number of packages you can add is subject to the value of Maximum Configured Packages in the cluster configuration file.

To create the package, follow the steps given in the chapter “Configuring Packages and Services.” If you are using the Serviceguard command line, however, do not specify the cluster ASCII file when verifying and distributing the configuration with HP-UX commands. For example, to use HP-UX commands to verify the configuration of newly created pkg1 on a running cluster:

# cmcheckconf -P /etc/cmcluster/pkg1/pkg1conf.ascii

Use an HP-UX command like the following to distribute the new package configuration to all nodes in the cluster:

# cmapplyconf -P /etc/cmcluster/pkg1/pkg1conf.ascii

Remember to copy the control script to the /etc/cmcluster/pkg1 directory on all nodes that can run the package.

Deleting a Package from a Running Cluster

In Serviceguard Manager, first halt the package. Then, select the cluster. From the Actions menu, choose Configuring Serviceguard -> Delete Package.

On the Serviceguard command line, you can delete a package from all cluster nodes by using the cmdeleteconf command. The command can only be executed when the package is not running; the cluster may be up. The command removes the package information from the binary configuration file on all the nodes in the cluster.

The following example halts package mypkg and removes the package configuration from the cluster:

# cmhaltpkg mypkg 
# cmdeleteconf -p mypkg

The command prompts for a verification before deleting the files unless you use the -f option. The directory /etc/cmcluster/mypkg is not deleted by this command.

Resetting the Service Restart Counter

The service restart counter is the number of times a package service has been automatically restarted. This value is used to determine when the package service has exceeded its maximum number of allowable automatic restarts.




	NOTE: The maximum number of allowable restarts for a given service is set in the package control script parameter `SERVICE_RESTART[]`. This parameter is not the same as the restart counter, which is maintained separately by the package manager.

When a package service successfully restarts after several attempts, the package manager does not automatically reset the restart count. However, you may choose to reset the counter online using the cmmodpkg -R -s command, thus enabling the service in future restart situations to have the full number of restart attempts up to the configured SERVICE_RESTART count. Example:

# cmmodpkg -R -s myservice pkg1

The current value of the restart counter may be seen in the output of the cmviewcl -v command.

Allowable Package States During Reconfiguration

All nodes in the cluster must be powered up and accessible when making configuration changes.

Refer to Table 7-2 “Types of Changes to Packages ” to determine whether or not the package may be running while you implement a particular kind of change. Note that for all of the following cases the cluster may be running, and also packages other than the one being reconfigured may be running.

Table 7-2 Types of Changes to Packages

Change to the Package	Required Package State
Add a new package	Other packages may be in any state.
Delete a package	Package must not be running.
Add a service	Package must not be running.
Remove a service	Package must not be running.
Add a subnet	Package must not be running. Subnet must already be configured into the cluster.
Remove a subnet	Package must not be running.
Add a resource	Package must not be running.
Remove a resource	Package must not be running.
Add a volume group	Volume group may be configured into the cluster while the cluster is running. The package may be in any state, because the change is made in the control script. However, the package must be halted and restarted for the change to have an effect.
Remove a volume group	Package must not be running.
Change run script contents	It is recommended that the package be halted. If the run script for the package is modified while the package is running, timing may cause problems.
Change halt script contents	It is recommended that the package be halted. If the halt script for the package is modified while the package is running, timing may cause problems.
Script timeouts	Package may be either running or halted.
Service timeouts	Package must not be running.
Service failfast	Package must not be running.
Package AutoRun	Package may be either running or halted.
Local LAN Failover	Package may be either running or halted.
Change the order of nodes where a package may run	Package may be either running or halted.
Change the Package Failover Policy	Package may be either running or halted.
Change the Package Failback Policy	Package may be either running or halted.
Change access policy	Package may be either running or halted.