Planning Which UFS File Systems to Back Up (System Administration Guide: Devices and File Systems)

System Administration Guide: Devices and File Systems

Planning Which UFS File Systems to Back Up

You should back up all file systems that are critical to users, including file systems that change frequently. The following tables provide general guidelines on the file systems to back up for stand-alone systems and servers.

Table 24–2 File Systems to Back Up for Stand-alone Systems


File System to Back Up	Description	Back Up Interval
root (`/`) – slice 0	This file system contains the kernel and possibly the `/var` directory. The `/var` directory contains temporary files, logging files, or status files, and possibly contains frequently updated system accounting and mail files.	At regular intervals such as weekly or daily
`/usr` – slice 6, `/opt`	The `/usr` and `/opt` file systems contain software and executables. The `/opt` directory is either part of root (`/`) or is its own file system.	Occasionally
`/export/home` – slice 7	This file system can contain the directories and subdirectories of all users on the stand-alone system.	More often than root (`/`) or `/usr`, perhaps as often as once a day, depending on your site's needs
`/export`, `/var`, or other file systems	The `/export` file system can contain the kernel and executables for diskless clients. The `/var` directory contains temporary files, logging files, or status files.	As your site requires

Table 24–3 UFS File Systems to Back Up for Servers


File System to Back Up	Description	Back Up Interval
root (`/`) – slice 0	This file system contains the kernel and executables.	Once a day to once a month depending on your site's needs. If you frequently add and remove users and systems on the network, you have to change configuration files in this file system. In this case, you should do a full backup of the root (`/`) file system at intervals between once a week and once a month. If your site keeps user mail in the `/var/mail` directory on a mail server, which client systems then mount, you might want to back up root (`/`) daily. Or, backup the `/var` directory, if it is a separate file system.
`/export` – slice 3	This file system can contain the kernel and executables for diskless clients.	Once a day to once a month, depending on your site's needs. Because the information in this file system is similar to the server's root directory in slice 0, the file system does not change frequently. You need to back up this file system only occasionally, unless your site delivers mail to client systems. Then, you should back up `/export` more frequently.
`/usr` – slice 6, `/opt`	The `/usr` and `/opt` file systems contain software and executables. The `/opt` directory is either part of root (`/`) or is its own file system.	Once a day to once a month, depending on your site's needs. These file systems are fairly static unless software is added or removed frequently.
`/export/home` – slice 7	This file system can contains the home directories of all the users on the system. The files in this file system are volatile.	Once a day to once a week.