Backup (UNIX and Linux): Additional considerations
There are some special situations that you need to consider
before you back up your data.
Stored files
When you back up and archive files, Tivoli Storage Manager stores
the backups and archives in a file space in storage that has the same
name as the file system or virtual mount point from which the files
originated.
Special file systems
Special file systems contain dynamic information generated
by the operating system; they contain no data or files. The Tivoli Storage Manager client
ignores special file systems and their contents.
NFS or virtual mount points
When files are backed up and archived from a file system
or virtual mount point, Tivoli Storage Manager does
not follow the nested NFS or virtual mount points (if any are defined
on a file system). The nested NFS or virtual mount points will not
be backed up or archived.
Management classes Tivoli Storage Manager uses
management classes to determine how to manage your backups on the
server.
Back up symbolic links Tivoli Storage Manager backs
up symbolic links differently than it does regular files and directories.
Hard links
When you back up files that are hard-linked, Tivoli Storage Manager backs
up each instance of the linked file.
Sparse files
Sparse files do not have disk space allocated for every
block in the whole address space, leading to holes within the file.
Holes are detected by their content, which is always zeros, and these
zeros take up space.
NFS hard and soft mounts
When Tivoli Storage Manager connects
a backup-archive client to an NFS file system, you can use either
a hard mount or a soft mount.
Deleted file systems
When a file system or drive has been deleted, or it is
no longer backed up by Tivoli Storage
Manager, the existing backup versions for each file are managed according
to the following policy attributes: Number of days to keep inactive
backup versions, and number of days to keep the last backup version
(if there is no active version)
Opened files Tivoli Storage Manager looks
for files that have changed between the start and the completion of
the backup of the file.
Wildcard characters
You can use the operating system wildcard characters in
file specifications with Tivoli Storage Manager. These
characters let you select groups of files that have similar names.