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 backup-archive 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, the client 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
The backup-archive client backs up symbolic links differently than it does regular files and directories. - Hard links
When you back up files that are hard-linked, the backup-archive client 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 the backup-archive client connects 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 the backup-archive client, 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
The backup-archive client 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 the backup-archive client. These characters let you select groups of files that have similar names.