Question about DDS drives and Make Recovery Tapes

[maria paschali]

Hi all,

I have 2 A-classes both running 11.0. One is my production box and the other is my development box which I am about to set up. I want to make my development box a replica of the production box.

I have one DDS drive attached to the production box.

Question 1
I want to know weather or not DDS are hot swappable. I.E. If I can basically pull it out of my production box and insert it into my development box?

Question 2
If I can't hot swap the DDS drive, can I get the development box to boot off the DDS drive remotely?

The reason I want to do this is to 1) test my make recovery tape and 2) Make an exact copy of my production environment.

Question 3
If my production box has different disk configuration to my development box will the make recovery tape still work?

Thanks in advance for all your help.

Maria

[Michael Tully]

Hi Maria,

Firstly it is possible to remove the tape
drive from one system and attach it to the
other as long as there is no traffic actually
on that SCSI chain. It is not something that
I would doing to a production box. You will
not be able to boot off a remote tape drive.
You have two alternate things that you could
do. One is to create a bootable depot or to
create a bootable CD.

http://www.docs.hp.com/hpux/onlinedocs/B2355-90704/B2355-90704.html
Chapter 8

The best way to create the tape in your case
would in interactive mode so that you can change the defaults on boot up of the tape should that be the way you choose.

# make_tape_recovery -x inc_entire=vg00 -I -a /dev/rmt/0mn

HTH
-Michael

[Andreas D. Skjervold]

Hi
Maybe you can use something we're planning on; but it will cost you some buck though.

To create a hotswap solution with one DDS tapedrive to serve 5 servers we plan to get inplace a rack enclosure with each slot wired to each of the 5 servers and one DAT to swap:

C4318B Smart Full Height Enclosure 3x4
C6365A SMART Field int. SE DDS3 DAT module
This will allow us to swap inbetween servers without buying 5 DAT drives.

Not to sure on the costs, but approx $2000 for the lot.

Andreas

[maria paschali]

Hi Andreas,

that sounds great. I have my 2 A-classes in the same smart enclosure, my dds drive sits on top of the enclosure with my monitor and 2-cdrom drives. If I can get them both to boot off it. That would be swell.

Any possible way I could get more info on how you wired them together?

Thanks

[Sanjay_6 · Accepted solution]

Hi Maria,

The way to share a SCSI device is that once cable to the device comes from one server and the other cable comes from the other server.

Server 1--> Port 1 of the Device --> Server 2.

If there is only one port on the device you use a V cable. Most of the external devices have 2 ports, one where the cable comes from one server and the other where it gets terminated. If you want to connect that device to another server, then in palce of terminating it, let the cable come from another server to that port. Only make sure that there is no SCSI address clash on the bus.

Hope this helps.

Thanks

[Carlos Fernandez Riera]

1- Yes you can change your drive. Just power off before unplug.


Even if your disk in delvopment box was smaller, recovery will run. Try automated restore first. If it is not posible to recover, the software will change to interactive. Then you will be able to change same configuration.

[Andreas D. Skjervold]

Hi Maria
Just like Sanjay says; 1 cable from each server to each port on the device.

Andreas

[A. Clay Stephenson]

Hi Maria:

One VERY important point is that if you are going to connect two hosts on the same SCSI bus, you MUST change the SCSI ID of one of the controllers. The default value is 7 and the most common value ti change the other one to is 6 - the next highest priority on the bus.

e.g.

HostA (SCSI ID 7) --- Tape Drive (SCSI ID 0, e.g.) --- Host B (SCSI ID 6). The termination should be enabled on each hoost's controller and no other termination should be used.