Managing HP Serviceguard for Linux, Tenth Edition, September 2012

available on the chosen node. One resource is the subnet that is monitored for the
package. If the subnet is not available, the package cannot start on this node. Another
type of resource is a dependency on another package. If monitoring shows a value for
a configured resource that is outside the permitted range, the package cannot start.
Once a node is selected, a check is then done to make sure the node allows the package
to start on it. Then services are started up for a package by the control script on the
selected node. Strictly speaking, the run script on the selected node is used to start a
legacy package; the master control script starts a modular package.
During Run Script Execution
Once the package manager has determined that the package can start on a particular
node, it launches the script that starts the package (that is, a package’s control script or
master control script is executed with the start parameter). This script carries out the
following steps:
1. Executes any external_pre_scripts (modular packages only; see “About
External Scripts” (page 147))
2. Activates volume groups or disk groups.
3. Mounts file systems.
4. Assigns package IP addresses to the LAN card on the node (failover packages only).
5. Executes any customer-defined run commands (legacy packages only; see “Adding
Customer Defined Functions to the Package Control Script ” (page 276)) or
external_scripts (modular packages only; see “About External Scripts”
(page 147)).
6. Starts each package service.
7. Exits with an exit code of zero (0).
How Packages Run 61