tunrestore Command

The tunrestore command is used to restore all the parameters from a file.

The following is the syntax for the tunrestore command:

tunrestore -R | [-r [-K]] -f filename

The following example changes the current values for all tunable parameters present in the file if ranges, dependencies, and incremental parameter rules are all satisfied.

tunrestore -f mytunable

tunrestore -f /etc/tunables/mytunable

In case of problems, only the changes possible will be made.

The following example changes the reboot values for all tunable parameters present in the file if ranges and dependencies rules are all satisfied. In other words, they will be copied to the /etc/tunables/nextboot file.

tunrestore -r -f mytunable

The following example changes the values for all tunable parameters that are present in the specified file and associated with the next boot and Live Update operations if ranges and dependency rules are satisfied. The values of the tunable parameters are copied to the /etc/tunables/nextboot and /etc/tunables/nextliveupdate files.

tunrestore -r -K -f mytunable

If changes to parameters of type bosboot are detected, the user will be prompted to run the bosboot command.

The following command can only be called from the /etc/inittab file and changes tunable parameters to values from the /etc/tunables/nextboot file.

tunrestore -R

Any problem found or change made is logged in the /etc/tunables/lastboot.log file. A new /etc/tunables/lastboot file is always created with the list of current values for all parameters. Any change to restricted tunable parameters from their default values will cause the addition of an error log entry identifying the list of these modified tunable parameters.

If filename does not exist, an error message displays. If the nextboot file does not exist, an error message displays when you use the -r flag. If the nextliveupdate file does not exist, an error message is displayed when you use the -K flag. If you use the -R flag, all the tuning parameters of a type other than bosboot will be set to their default value, and a nextboot file containing only an info stanza will be created. A warning will also be logged in the lastboot.log file.

Except when -r is used, parameters requiring a call to bosboot and a reboot are not changed, but an error message is displayed to indicate they could not be changed. When -r is used, if any parameter of type bosboot needs to be changed, the user will be prompted to run bosboot. Parameters missing from the file are simply left unchanged, except when -R is used, in which case missing parameters are set to their default values. If the file contains multiple entries for a parameter, only the first entry will be applied, and a warning will be displayed or logged (if called with -R).