/0mn and /0m

[khilari]

Okay guys, so just confirming something. If i want to take a backup using tar i will use the /0mn option because i want to rewind. But when i am taking an ignite image i will use /0m only because i dont want a rewind to occur. Thanks

[Carlos Roberto Schimidt]

Hi,

The letter "n" means no-rewind, so /0mn is used to no rewind tape.

Schimidt

[Steven E. Protter]

Shalom khilari,

I don't think you are going to be able to get two usable Ignite images on the tape, but if you use the device with an n, no rewind will occur and you might be able to write more to that tape.

An ignite image however consists of several images, one of which boots the system for example.

SEP

[Patrick Wallek]

You've got it exactly backwards.

0m = rewind

0mn = no-rewind

[Bill Hassell]

It's important to note that the rewind and no-rewind device files only have meaning when simple programs do nothing to position the tape (for example, tar, cpio, etc). fbackup explicitly rewinds a tape prior to backup and also at the end of a backup, regardless of the device file. Similarly, Ignite/UX always starts at the beginning of a tape. It is not possible to position a tape with processor commands so only one Ignite image per tape. Use the lssf command to decode the names:

lssf /dev/rmt/*

[Yogeeraj_1 · Accepted solution]

hi,

A no rewind device would end in "n" in the device name.

e.g. /dev/rmt/0mn
The above is the no-rewind device file for /dev/rmt/0m.

This is the same tape drive, but if you use the "n" interface, the tape *won't* automatically rewind at the end of the operation.

So, if you keep a tape in the drive and use the no-rewind interface, you'll keep appending to the tape, instead of overwriting.


kind regards
yogeeraj