IGNITE Tape verification with mstm?

[gnd]

Hello all, before restarting an failed ignite backup, i check if the tape in the drive is ok. I perform mstm verification on it, and if it was succesfull, i check the tape status with /dev/rmt/0mn stat
rewind the tape with mt -f /dev/rmt/0mn rew
and then restart.
Anyway i have some questions about the way the ignite backup works with the tape:

1. Is Ignite Backup Sequential - eg. On one tape there are more archives - differing by time done ?
2. mt -f /dev/rmt/?mn rew - Rewinds the tape on the beginning ? If the ignite is one backup/one tape then you rewrite the tape with the previous backup?
3. What does mt -f /dev/rmt/?mn -fsf 1 command do? What exactly means Forward space 1 files ? Used by the recovery of files from the tape.
4. Does ignite backup rewind the tape when finished?

All this is connected to the nature of the mstm check, which performs random write checks on the tape (destroying its content)..

[Ivajlo Yanakiev]

HI qnd

Ingnite create one archive and replace all old archive. this is general.
If you not use mt command.
Mt give you way to read files on tape.
On ignite tape you have 2 files.
Firts is binary boot files.
Second is your VG00 system archive.
You can test your archive using

mt -f /dev/rmt/?mn -fsf 1
move your tape one files
and
tar -tvf /dev/rmt/?mn

also remember that if you put or remove your tape from tape device it will rewind

[Bill Hassell]

1. The Ignite tape has two files: the raw kernel data needed to boot from the tape, and the second is a pax backup of VG00. You cannot have multiple Ignite backups on one tape because it's sole purpose is to restore install HP-UX (VG00). On a dead machine, there is no way to position the tape for bootup so there is no way to bring a different copy of an Ignite backup from tape.

2. mt ... rew indeed rewinds the tape. AS mentioned in the above comments, there can be only one Ignite backup per tape.

3. mt ... fsf 1 indeed spaces over the bootable portion of the Ignite backup (which is file 1) and allows you to run pax to restore some selected files.

4. Ignite should rewind the tape, and you should immediately remove the tape to prevent accidental writes to the recovery tape.

mstm will perform destructive tests on a write-enabled tape. To check the contents of an Ignite tape, you can use dd to read the tape.