HP Serviceguard manual Differences between Failover and Multi-Node Packages, Base Package Modules

Differences between Failover and Multi-Node Packages

Note the following important differences in behavior between multi-node and failover packages:

•If a multi-node package has auto_run disabled (set to no in the package configuration file) it will not start when the cluster is started. You can use cmmodpkg to enable package switching and start the package for the first time. But if you then halt the multi-node package via cmhaltpkg, it can be re-started only by means of cmrunpkg, not cmmodpkg.

•If a multi-node package is halted via cmhaltpkg, package switching is not disabled. This means that the halted package will start to run on a rebooted node, if it is configured to run on that node and its dependencies are met.

•When a multi-node package is started the first time (either at cluster startup, or subsequently if auto_run is set to no, and package switching is then enabled) any dependent package will start on its primary node. But if a multi-node package is halted along with its dependent packages, and the multi-node package is then restarted, dependent packages which have had package switching re-enabled will start on the first eligible node on which an instance of the multi-node package comes up; this may not be the dependent packages’ primary node.

To ensure that dependent failover packages restart on their primary node if the multi-node packages they depend on need to be restarted, make sure the dependent packages’ package switching is not re-enabled before the multi-node packages are restarted. You can then either restart the dependent failover packages with cmrunpkg, specifying the node you want them to start on, or enable package switching for these packages after the multi-node package startup is complete.

Package Modules and Parameters

The table that follows shows the package modules and the configuration parameters each module includes. Read this section in conjunction with the discussion under “Package Configuration Planning ” (page 125).

Use this information, and the parameter explanations that follow ((page 233)), to decide which modules (if any) you need to add to the failover or multi-node module to create your package. If you are used to creating legacy packages, you will notice that parameters from the package control script (or their equivalents) are now in the package configuration file; these parameters are marked

(S) in the table.

You can use cmmakepkg -l(letter “l”) to see a list of all available modules, including non-Serviceguard modules such as those supplied in the HP Toolkits.

NOTE: If you are going to create a complex package that contains many modules, you may want to skip the process of selecting modules, and simply create a configuration file that contains all the modules:

cmmakepkg -m sg/all $SGCONF/sg-all

(The output will be written to $SGCONF/sg-all.)

Base Package Modules

At least one base module (or default or all, which include the base module) must be specified on the cmmakepkg command line. Parameters marked with an asterisk (*) are new or changed as of Serviceguard A.11.18 or A.11.19. (S) indicates that the parameter (or its equivalent) has moved from the package control script to the package configuration file for modular packages. See the “Package Parameter Explanations” (page 233) for more information.

230 Configuring Packages and Their Services