A file system is a complete directory structure, including a root directory and any subdirectories and files beneath it. File systems are confined to a single logical volume. Some of the most important system management tasks are concerning file systems, specifically:
Following is a list of system management commands that help manage file systems:
| backup | Performs a full or incremental backup of a file system |
| chfs -a splitcopy | Creates an online backup of a mounted JFS file system |
| dd | Copies data directly from one device to another for making file system backups |
| df | Reports the amount of space used and free on a file system |
| fsck | Checks file systems and repairs inconsistencies |
| mkfs | Makes a file system of a specified size on a specified logical volume |
| mount | Attaches a file system to the system-wide naming structure so that files and directories in that file system can be accessed |
| restore | Restores files from a backup |
| snapshot | Creates a snapshot of a JFS2 file system |
| umount | Removes a file system from the system-wide naming structure, making the files and directories in the file system inaccessible. |
There are a number of commands designed to operate on file systems, regardless of type. The /etc/filesystems file controls the list of file systems that the following commands can manipulate:
| chfs | Changes the characteristics of a file system |
| crfs | Adds a file system |
| lsfs | Displays the characteristics of a file system |
| rmfs | Removes a file system |
| mount | Makes a file system available for use |
Four commands operate on virtual file systems types. The /etc/vfs file contains the information on the file system types that the following commands manipulate:
| chvfs | Changes the characteristics of a file system type |
| crvfs | Adds a new file system type |
| lsvfs | Lists the characteristics of a file system type |
| rmvfs | Removes a file system type |