use both port on A5159A SCSI card instead of 1

[Carol Yu]

Hi, All,

I have an A5159A dual port Differential Ultra SCSI card. Now I am using only 1 port to connect to SUn Storedge D1000 disk array. D1000 disk array can be used as a whole piece or two seperate pieces as it has 2 connectors on it.

I want to change the setting to use both ports of A5159A card for performance issue. Will this affect anything? Will this affect the physical address of the disks in disk array and cause problem for vgs and lvols?

Here is part of the list from ioscan:
0/4/2/0 ext_bus SCSI C87x Fast Wide Differential
0/4/2/0.0 target
0/4/2/0.0.0 disk SEAGATE ST3146807LC
0/4/2/0.1 target
0/4/2/0.1.0 disk SEAGATE ST3146807LC
0/4/2/0.2 target
0/4/2/0.2.0 disk SEAGATE ST3146807LC
0/4/2/0.3 target
0/4/2/0.3.0 disk SEAGATE ST3146807LC
0/4/2/0.4 target
0/4/2/0.4.0 disk SEAGATE ST3146807LC
0/4/2/0.7 target
0/4/2/0.7.0 ctl Initiator
0/4/2/0.8 target
0/4/2/0.8.0 disk SEAGATE ST3146807LC
0/4/2/0.9 target
0/4/2/0.9.0 disk SEAGATE ST3146807LC
0/4/2/0.10 target
0/4/2/0.10.0 disk SEAGATE ST3146807LC
0/4/2/0.11 target
0/4/2/0.11.0 disk SEAGATE ST3146807LC
0/4/2/0.14 target
0/4/2/0.14.0 ctl SYMBIOS D1000
0/4/2/0.15 target
0/4/2/0.15.0 ctl SYMBIOS D1000
0/4/2/1 ext_bus SCSI C87x Fast Wide Differential
0/4/2/1.7 target
0/4/2/1.7.0 ctl Initiator

Thanks a lot.

[Mel Burslan]

As far as the system configuration is concerned, nothing should change. But if you are using the whole array as one big lump of disk space, you will need to backup your data, split it into two parts accessible from two scsi channels (however this would beusing your particular disk array) then rebuild your LVM structure according to the new distribution, then restore your data from the backups.

This is the most trivial way of doing it.

[Clay Jones_2]

I'm not sure about logical volume manager, but Veritas Volume Manager (now included with HPUX) has a concept know as "Dynamic Multipathing" that allows you to write to disk over two controllers, both for failover and throughput enhancement.

[Carol Yu]

Thanks for your reply. I want to present more info so we can have a closer look at this.

Actually this disk storage D1000 is setup with another HP-UX server that got lost during shipping. I had HP helped me to re-import the vgs to my new server. As far as I know that those vgs are mirrored. My guess is the D1000 as used with 2 controllers /ports when it setup, one is for mirror. But mirror won't work now since I am still waiting for my mirror software to come and then I can install on the new server.

In this case, what should I do? I plan to shut down the disk storage and server and change the cabling, and set the disk storage and boot server up. Is there anything else I need to do?

Thanks a lot,
Carol