DRD-Safe Commands and Packages

The drd runcmd operation runs a command on the inactive system image that does not make any changes to the booted system, the running kernel, or the process space. This enables a system administrator to make changes to the inactive system image without incurring any disruption to the currently booted system.

	NOTE: The drd runcmd command suppresses all reboots. The option -x autoreboot is ignored when a swinstall or swremove command is executed by drd runcmd.

Not all commands can safely be executed by the drd runcmd operation. For example, commands that start or stop daemons or change dynamic kernel tuneables are disruptive to current processes and must be prevented by the drd runcmd operation.

Restrictions on commands executed by drd runcmd are:

Commands that are not disruptive to the booted system and perform appropriate actions on the inactive system are known as DRD-safe. For this release of DRD, a short list of commands is recognized by the drd runcmd operation to be DRD-safe. An attempt to use DRD to run commands that are not DRD-safe will terminate with an ERROR return code without executing the command.

A number of Software Distributor commands have been made safe at a sufficient maintenance level of SW-DIST. The DRD product has a package co-requisite on a minimum release of SW-DIST. (For details of the DRD product dependencies, see the following Web page: http://docs.hp.com/en/DRD/patch.html.)

The DRD-safe commands are the following:

See the Software Distributor Administrator's Guide, located at http://docs.fc.hp.com/en/oshpux11iv2.html#System%20Administration, as well as swinstall(1M), swremove(1M), swlist(1M), swmodify(1M), swverify(1M), swjob(1M), kctune(1M), and view(1M) for additional information about these commands.

The DRD-safe commands may be specified by their base names, such as swinstall or swremove, or their full paths, such as /usr/sbin/swinstall or /usr/sbin/swremove. However, paths that are symlinks to the DRD-safe commands are not supported.

If the inactive system image has not been mounted, the drd runcmd operation mounts it, executes the DRD-safe command, and then unmounts it. If the inactive system image is already mounted, the drd runcmd operation leaves it mounted.

When swinstall and swremove are used to manage software packages, SD control scripts included in the packages, such as pre-install and post-remove scripts, are executed. For management of such packages to be DRD-safe, the control scripts themselves must not take any action that will affect the booted system. (The configure scripts are not executed.) A package satisfying this restriction is also known as DRD-safe. The swlist, swmodify, and swverify commands—without -F or -x fix=true options—may be invoked by drd runcmd for arbitrary packages. The swlist and swmodify commands do not call control scripts, and verify scripts do not change the system.

When executing the drd runcmd kctune command, the kctune command outputs the prompt:

If the user types y, the following error is displayed:

WARNING: The backup behavior 'yes' is not supported in alternate
         root environments.  The behavior 'once' will be used instead.

This message can be ignored.