on 09-04-2009 11:26 AM
I have seen this topic come up numerous times in the forums and thought it was worth writing a short article to explain NetBackup behavior when specifying / in the backup selections list for a Solaris client. I realize this is a topic alot of people are familiar with but due to the number of forum entries asking the question I'll try to make this as straight forward as possible for those who need clarification.
If you specify / in your backup selections list (and only /), you will not get /var or /opt if they are on a different filesystem (unless you check "cross mount points" in the policy attributes). To be more specific lets say we're working with a system disk that has the path /dev/dsk/c0t0d0.
Most Solaris people will know that this physical disk can have up to 7 usable slices (0-7 minus slice 2 ). If you only use one partition for your operating system (which is not considered best practice) and put everything on one slice then specifying / in your backup selections list will backup the entire OS as everything under / is all on one filesystem. This will not backup any other filesystems (that live on different disks) that may be mounted under / in your directory tree.
However if you have different filesystems on different partitions of your system disk then you will need cross mount points checked. For example a disk that is set up like so:
/ = c0t0d0s0
/usr = c0t0d0s3
/var = c0t0d0s4
/data = c0t0d0s5
With the disk partitioned as it is above, specifying / in your backup selections list, without checking "cross mount points" in the policy attributes tab, will only backup /. It will not backup /usr, /var, or /data as they live on seperate filesystems and are merely mounted to a mount point on the root filesystem (cross mount points). So you would either need to check "cross mount points" in order to back them up, or list them seperately.
The same goes for any other filesystem not on your system disk. For example if you have a filesystem that lives on a seperate internal disk, or an external disk for that matter, again these will not be backed up by specifying / only in the backup selections list unless you check cross mount points or list them seperately on the backup selections list.
Below is an excerpt from the admin guide:
Cross Mount Points
The Cross Mount Points policy attribute applies only to certain policy types and
NetBackup allows you to select it in only those instances.
The Cross Mount Points policy attribute controls whether NetBackup crosses file system
boundaries during a backup or archive on UNIX clients or whether NetBackup enters
volume mount points during a backup or archive on Windows clients.
◆ If you select Cross Mount Points, NetBackup backs up or archives all files and
directories in the selected path, regardless of the file system. For example, if you
specify root (/) as the file path, NetBackup backs up root (/) and all files and
directories under it in the tree. Usually, this means all the client’s files, other than
those available through NFS.
◆ If you clear Cross Mount Points, NetBackup backs up or archives only files and
directories that are in the same file system as the selected file path. This lets you back
up a file path such as root (/) without backing up all the file systems that are mounted
on it (for example, /usr and /home).
Notes on Cross Mount Points
◆ Cross Mount Points has no effect on UNIX raw partitions. If the raw partition that is
being backed up is the root partition and has mount points for other file systems, the
other file systems are not backed up even if you select Cross Mount Points.
Sorry if posting to an old thread....
If you have zones installed on your Solaris 10 server, the "ALL_LOCAL_DRIVES" actually ends up backing up the zones multiple times. If you specify only just "/", the zones are backed up with no issues. Just make sure in the policy, you check "Cross mount points" as the article says or you will not get the zones backed up.
What is the impact if ALL_LOCAL_DRIVES and Cross Mount Points are both used simultaneously.