Mounting and unmounting RD1000 cartridges

[Alessandro FAGLIA]

Hi list.

I'm a bit troubled with RD1000 cartridges and how to manage 
mounting/unmounting them.

When I boot my server with RD1000 attached, I can see the unit's been 
recognized in /var/log/messages:

> Nov  6 16:17:51 prsrv003 kernel: scsi 2:0:0:0: Direct-Access     
> DELL     RD1000           2030 PQ: 0 ANSI: 3
> Nov  6 16:17:51 server kernel: sd 2:0:0:0: [sdd] 312573616 512-byte 
> hardware sectors (160038 MB)
> Nov  6 16:17:51 server kernel: sd 2:0:0:0: [sdd] Write Protect is off
> Nov  6 16:17:51 server kernel: sd 2:0:0:0: [sdd] 312573616 512-byte 
> hardware sectors (160038 MB)
> Nov  6 16:17:51 server kernel: sd 2:0:0:0: [sdd] Write Protect is off
> Nov  6 16:17:51 server kernel:  sdd: sdd1

If I issue the eject command, the disk is unmounted and ejected as expected.

The problem arises when I try to mount it again. Whenever I plug the 
disk in the unit I cannot see any message in the log, and also 
udevmonitor does not show any event (this prevents me to write udev 
rules in order to assign a friendly name to the unit, e.g. 
dell_cartridge). Sometimes the mount command works (mount -t reiserfs 
/dev/sdd1 /mnt/backup), but sometimes it does not:

> server:~# mount -t reiserfs /dev/sdd1 /mnt/backup/
> mount: special device /dev/sdd1 does not exist

It seems the system does not know that I've plugged the tape. If I issue 
a wrong command:

> server:~# mount -t reiserfs /dev/sdd /mnt/backup/

then the log is populated as follows:

> Nov  7 10:05:08 server kernel: sd 5:0:0:0: [sdd] Spinning up 
> disk.....<5>sd 5:0:0:0: [sdd] 312573616 512-byte hardware sectors 
> (160038 MB)
> Nov  7 10:05:08 server kernel: sd 5:0:0:0: [sdd] Write Protect is off
> Nov  7 10:05:08 server kernel: sd 5:0:0:0: [sdd] 312573616 512-byte 
> hardware sectors (160038 MB)
> Nov  7 10:05:08 server kernel: sd 5:0:0:0: [sdd] Write Protect is off
> Nov  7 10:05:09 server kernel:  sdd: sdd1
> Nov  7 10:05:09 server kernel: ReiserFS: sdd: warning: sh-2021: 
> reiserfs_fill_super: can not find reiserfs on sdd

Now the system has found the disk, and the mount is successfull:

> Nov  7 10:08:10 server kernel: ReiserFS: sdd1: found reiserfs format 
> "3.6" with standard journal
> Nov  7 10:08:10 server kernel: ReiserFS: sdd1: using ordered data mode
> Nov  7 10:08:10 server kernel: ReiserFS: sdd1: journal params: device 
> sdd1, size 8192, journal first block 18, max trans len 1024, max batch 
> 900, max commit age 30, max trans age 30
> Nov  7 10:08:10 server kernel: ReiserFS: sdd1: checking transaction 
> log (sdd1)
> Nov  7 10:08:10 server kernel: ReiserFS: sdd1: Using r5 hash to sort names

Provided I'm going to mount/unmount it inside shell scripts, could 
anybody give me best practices on how to manage the mounting/unmounting 
procedure?
Is it possibile to force a rescan of scsi bus in order to tell the 
system that a new device has been added?


TIA
-- Alessandro