Tape Drive DEVICE FILE

[meekrob]

Hi ,
i have connected e HP StorageWorks 5300 to a rp3440 server ,
but the device file of the tape drive created is c2t5d0BEST and not /dev/rmt/0m ,
or my application use the /dev/rmt/0m and 0mn to do the backup ,
how should i convert the c2t5d0BEST device file to /dev/rmt/0m
thank you

[A. Clay Stephenson]

Do an "ls -l /dev/rmt/c2t5d0" and note the major and minor device number for each device listed.

Next, "rm /dev/rmt/0*"

Finally, use mknod to create devices with the same major and minor device numbers as their c2t5d0 counterparts.

For example, let's assume that /dev/rmt/c2t5d0BEST is major 205 and minor 0x025000.

mknod c /dev/rmt/0m 203 0x025000

[Pete Randall]

This is one of those questions that gets asked often enough, I documented the complete answer:



First, let me echo Bill Hassell in saying you can simply rename the existing dev
ice file. There is no significance other than historical to the device names as
we know them.

Second, if you're still nervous about it, you can use a link - linking the undes
ired name to the preferred name.

Third, if you really want to re-create the device names properly, here is a guid
e:

1. Use "ioscan" to find out what the current device files look like and what th
e instance number is:
ioscan -kfnCtape


2. Use "mksf" to create each of the four types of device files:

/sbin/mksf -d stape -I 12 -a -b BEST rmt/12m
/sbin/mksf -d stape -I 12 -u -b BEST rmt/12mb
/sbin/mksf -d stape -I 12 -a -n -b BEST rmt/12mn
/sbin/mksf -d stape -I 12 -u -n -b BEST rmt/12mnb


3. Use "ll" to compare your newly created device files with those created by the
system. Major and minor numbers should match between corresponding entries (205
0x061000 for both 12m and the equivalent c6t1d0BEST):

ll /dev/rmt |more

crw-rw-rw 1 bin bin 205 0x061000 Mar 17 08:40 12m
.
.
.
crw-rw-rw 1 bin bin 205 0x061000 Mar 17 08:40 c6t1d0BEST
.
.
.



4. repeat the ioscan to double check that your new device files are associated w
ith the correct tape drive:

ioscan -kfnCtape



I was using 12m in the example but you can use anything you want.


Pete

[Peter Nikitka]

Hi,

I consider the device names '/dev/rmt/0*' as links to the default tape device.
If you have only one tape drive and the default does no longer fit, or want a different drive selected (having multiple tape drives) change the default:

- List all tape devices including device filenames:
ioscan -fnCtape

- remove the default tape device files:
rm /dev/rmt/0m /dev/rmt/0mn ...

- create new default device filenames, at least (source names may differ):
ln /dev/rmt/c2t5d0BEST /dev/rmt/0m
ln /dev/rmt/c2t5d0BESTn /dev/rmt/0mn

- List device information again:
ioscan -fnCtape

mfG Peter