How to create the same device files for SAN tapedevice on HP-UX

[VCD support]

Hello,

I have two hp-ux servers and two MSL6030 libraries with each two tape drives, connected to a san. On the first HP-UX server devices 1m, 2m, 5m and 6m are created for the tapedevices, on the other server 1m, 3m, 5m and 6m. Data Protector is installed in a mc/serviceguard package and I want to configure a tapedevice to a package that can run on one of the hp-ux servers. On both systems I must have the same tape device files, how can I do this?

Kind regards,
Lucas

[Luk Vandenbussche]

Hi,
Can you send the output of the directory /dev/rmt from both servers pls

[Kurt Beyers.]

Lucas,

The starting number is based on the instance number found in an ioscan.

Check that there is no old remaining special file left over on one of the two servers. You can if required also create a symbolic link to one of them to have the same tape drive on both servers.

Or use the multipath feature in DP 55 so that DP itself will correct the hardware path after a failover of the MCSG package to another node.

best regards,
Kurt

[VCD support]

output from /dev/rmt directory on hpux1:
crw-rw-rw- 2 bin bin 205 0x1e4300 Dec 21 09:28 1m
crw-rw-rw- 2 bin bin 205 0x1e4380 Dec 21 09:28 1mb
crw-rw-rw- 2 bin bin 205 0x1e4340 Dec 21 09:28 1mn
crw-rw-rw- 2 bin bin 205 0x1e43c0 Dec 21 09:28 1mnb
crw-rw-rw- 2 bin bin 205 0x1e4200 Dec 21 09:28 2m
crw-rw-rw- 2 bin bin 205 0x1e4280 Dec 21 09:28 2mb
crw-rw-rw- 2 bin bin 205 0x1e4240 Dec 21 09:28 2mn
crw-rw-rw- 2 bin bin 205 0x1e42c0 Dec 21 09:28 2mnb

output from /dev/rmt on hpux2:
crw-rw-rw- 2 bin bin 205 0x1e4300 Dec 21 09:29 1m
crw-rw-rw- 2 bin bin 205 0x1e4380 Dec 21 09:29 1mb
crw-rw-rw- 2 bin bin 205 0x1e4340 Dec 21 09:29 1mn
crw-rw-rw- 2 bin bin 205 0x1e43c0 Dec 21 09:29 1mnb
crw-rw-rw- 2 bin bin 205 0x1e4200 Dec 21 09:29 3m
crw-rw-rw- 2 bin bin 205 0x1e4280 Dec 21 09:29 3mb
crw-rw-rw- 2 bin bin 205 0x1e4240 Dec 21 09:29 3mn
crw-rw-rw- 2 bin bin 205 0x1e42c0 Dec 21 09:29 3mnb

As you can see on both servers are the minor and major numbers identical (we put the controllers on both servers on instance 30 with ioinit), but still, a device 3m is created on hpux2 and a device 2m is created on hpux1.

[Luk Vandenbussche]

Hi Lucas,

The most easiest way to solve this is


on hpux2

mv /dev/rmt/3m /dev/rmt/2m
mv /dev/rmt/3mb /dev/rmt/2mb
mv /dev/rmt/3mn /dev/rmt/2mn
mv /dev/rmt/3mnb /dev/rmt/2mnb

It will stil be ok after a reboot

[VCD support]

I used the option "Automatically discover changed SCSI adress" in Data Protector when creating the device on the first system. After switching the package to the second system, I started a backup, Data Protector could not write to the device, did a discovery, found new device with same serial number and backup began. I will use this option for all the tapedevices and leave the devices on hp-ux as they are. Thanx for the advice from you all.

Lucas

[VCD support]

see my last reply, found a workaround for the problem within the backup software