Managing file system
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:
- Allocating space for file systems on logical volumes
- Creating file systems
- Making file system space available to system users
- Monitoring file system space usage
- Backing up file systems to guard against data loss in the event of system failures
- Making a snapshot to capture a consistent block-level image of a file system at a given point in time
- Maintaining file systems in a consistent state.
Following is a list of system management commands that help manage file systems:
| Item | Description |
|---|---|
| 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. |