Synchronizing Files Between Boot Environments
When you are ready to switch and make the new boot environment active,
you quickly activate the new boot environment and reboot. Files are synchronized between
boot environments the first time that you boot a newly created boot environment.
“Synchronize” means that certain critical system files and directories might be copied from the
last-active boot environment to the boot environment being booted. Those files and directories
that have changed are copied.
Adding Files to the /etc/lu/synclist
Solaris Live Upgrade checks for critical files that have changed. If these files'
content is not the same in both boot environments, they are copied from
the active boot environment to the new boot environment. Synchronizing is meant for
critical files such as /etc/passwd or /etc/group files that might have changed
since the new boot environment was created.
The /etc/lu/synclist file contains a list of directories and files that are synchronized.
In some instances, you might want to copy other files from the active
boot environment to the new boot environment. You can add directories and files
to /etc/lu/synclist if necessary.
Adding files not listed in the /etc/lu/synclist could cause a system to become
unbootable. The synchronization process only copies files and creates directories. The process does
not remove files and directories.
The following example of the /etc/lu/synclist file shows the standard directories and files
that are synchronized for this system.
Examples of directories and files that might be appropriate to add to the
synclist file are the following:
The synclist file entries can be files or directories. The second field is
the method of updating that occurs on the activation of the boot environment.
You can choose from three methods to update files:
OVERWRITE – The contents of the active boot environment's file overwrites the contents of the new boot environment file. OVERWRITE is the default action if no action is specified in the second field. If the entry is a directory, all subdirectories are copied. All files are overwritten. The new boot environment file has the same date, mode, and ownership as the same file on the previous boot environment.
APPEND – The contents of the active boot environment's file are added to the end of the new boot environment's file. This addition might lead to duplicate entries in the file. Directories cannot be listed as APPEND. The new boot environment file has the same date, mode, and ownership as the same file on the previous boot environment.
PREPEND – The contents of the active boot environment's file are added to the beginning of the new boot environment's file. This addition might lead to duplicate entries in the file. Directories can not be listed as PREPEND. The new boot environment file has the same date, mode, and ownership as the same file on the previous boot environment.
Forcing a Synchronization Between Boot Environments
The first time you boot from a newly created boot environment, Solaris Live
Upgrade synchronizes the new boot environment with the boot environment that was last
active. After this initial boot and synchronization, Solaris Live Upgrade does not
perform a synchronization unless requested. To force a synchronization, you use the luactivate
command with the -s option.
You might want to force a synchronization if you are maintaining multiple versions
of the Solaris OS. You might want changes in files such as
email or passwd/group to be in the boot environment you are activating to.
If you force a synchronization, Solaris Live Upgrade checks for conflicts between files
that are subject to synchronization. When the new boot environment is booted and
a conflict is detected, a warning is issued and the files are not
synchronized. Activation can be completed successfully, despite such a conflict. A conflict
can occur if you make changes to the same file on both the
new boot environment and the active boot environment. For example, you make changes
to the /etc/passwd file on the original boot environment. Then you make other
changes to /etc/passwd file on the new boot environment. The synchronization process cannot
choose which file to copy for the synchronization.
Caution - Use this option with great care, because you might not
be aware of or in control of changes that might have occurred in
the last-active boot environment. For example, if you were running Solaris Express
5/07 software on your current boot environment and booted back to a Solaris
9 release with a forced synchronization, files could be changed on the Solaris
9 release. Because files are dependent on the release of the OS, the
boot to the Solaris 9 release could fail because the Solaris Express 5/07
files might not be compatible with the Solaris 9 files.