System Administration Guide: Devices and File Systems

Backup Device (dump-file) Argument

The dump-file argument (to the -f option) specifies the destination of the backup. The destination can be one of the following:

Use this argument when the destination is not the default local tape drive /dev/rmt/0. If you use the -f option, then you must specify a value for the dump-file argument.

Note –

The dump-file argument can also point to a file on a local disk or on a remote disk. If done by mistake, this usage can fill up a file system.

Local Tape or Diskette Drive

Typically, the dump-file argument specifies a raw device file for a tape device or diskette. When the ufsdump command writes to an output device, it creates a single backup file that might span multiple tapes or diskettes.

You specify a tape device or a diskette on your system by using a device abbreviation. The first device is always 0. For example, if you have a SCSI tape controller and one QIC-24 tape drive that uses medium-density formatting, use this device name:


When you specify a tape device name, you can also type the letter “n” at the end of the name to indicate that the tape drive should not rewind after the backup is completed. For example:


Use the “no-rewind” option if you want to put more than one file onto the tape. If you run out of space during a backup, the tape does not rewind before the ufsdump command asks for a new tape. For a complete description of device-naming conventions, see Backup Device Names.

Remote Tape or Diskette Drive

You specify a remote tape device or a remote diskette by using the syntax host:device. The ufsdump command writes to the remote device when superuser on the local system has access to the remote system. If you usually run the ufsdump command as superuser, the name of the local system must be included in the /.rhosts file on the remote system. If you specify the device as user@host:device, the ufsdump command tries to access the device on the remote system as the specified user. In this case, the specified user must be included in the /.rhosts file on the remote system.

Use the naming convention for the device that matches the operating system for the system on which the device resides, not the system from which you run the ufsdump command. If the drive is on a system that is running a previous SunOS release (for example, 4.1.1), use the SunOS 4.1 device name (for example, /dev/rst0). If the system is running Solaris software, use the SunOS 5.9 convention (for example, /dev/rmt/0).

Using Standard Output With the ufsdump Command

When you specify a dash (-) as the dump-file argument, the ufsdump command writes to standard output.

Note –

The -v option (verify) does not work when the dump-file argument is standard output.

You can use the ufsdump and ufsrestore commands in a pipeline to copy a file system by writing to standard output with the ufsdump command and reading from standard input with the ufsrestore command. For example:

# ufsdump 0f - /dev/rdsk/c0t0d0s7 | (cd /home; ufsrestore xf -)