Link from server to xp512

[Kenneth Yap]

Dear Experts,
How the link that the server have four FC card and connect to two FC switches and connect to xp512 ?
Can we do any load balancing for the four FC card in the server?
Let's said, I have card a,b,c,d.
I create card a for vg01 and card b is alternative.
Card b for vg02 and card c is alternative.
Card c for vg03 and card d ic alternative.
Card d for vg04 and card a is alternative.

Can above be configure ?
Any document that can be reference ?

[Alexander M. Ermes]

Hi there.
Check the load on the disks woth top, sar or glance. Take a look at the attached file.
It should give you and idea, how to spread the load across four channels.
Rgds
Alexander M. Ermes

[Sridhar Bhaskarla]

Kenneth,

Above can be configurable if you are able to see the LUNs on the selected cards.

For ex., you need to configure your LUN security for the LUNs appearing on the card a to be seen on card b. Or you can see all the LUNs appearing on all the cards so that it will flexible.

For ex., if the LUN security is configued such that you can see all the LUNs on all the interfaces like this

card-a card-b card-c card-d
c0t0d0 c1t0d0 c2t0d0 c3t0d0
c0t0d1 c1t0d1 c2t0d1 c3t0d1
c0t0d2 c1t0d2 c2t0d2 c3t0d2

Create vg01 with the LUN c0t0d0 and extend the volume group with the LUN c1t0d0.
Create vg02 with the LUN c1t0d1 and extend the volume group with the LUN c2t0d1
Create vg03 with the LUN c2t0d2 and extend the volume group with the LUN c3t0d1
Create vg04 with the LUN c3t0d2 and extend the volume group with the LUN c0t0d2


I hope you understood the logic.

-Sri

[Kenneth Yap]

Hi all,
Is the any way to configure the all the FC cards that link to the xp are load balancing ?
That's means for one vg , vg01 its using all the cards include the alternative card and no standby or alternate link.

[Ovidiu D. Raita]

You'd have to buy "auto path xp". Follow the link below:

http://www.hp.com/products1/storage/disk_arrays/xpstoragesw/autopathxp/overview_features.html

Ovidiu

[Sridhar Bhaskarla]

Kenneth,

I would go for extent level striping to balance the fiber channels loads. There is no otherway with the default LVM.

You need to go for auto path or Veritas Volume manager if you want automatic load balancing on the paths.

-Sri

[Kenneth Yap]

Can the auto path operate without the server connect to xp storage ?

Can the auto path operate stand alone to manage the scsi card for load balansing ?

[Oliver Haensel]

Hi Kenneth,

NO! Autopath is customized for a specific hardware product (currently available for VA diskarray). If you want to use loadbalancing with HP-UX product independendly you need to have Veritas Volume Manager (is supported with HP-UX 11i..)

Hope that helps

-Oliver-

[Sridhar Bhaskarla]

Autopath is only XP subsystems. That's why it's called autopath-xp. It will not work for other arrays.

-Sri

[Samir Mehta]

Hi Mr.Kenneth,

You can plan your LVM layout as suggested by Sri so that every Logical Volume, note logical volume is apanning across the PVs from all the four controllers. that means you have to assign LUNs accordingly.. For example, you may assign 4 LUNs to 4 controllers and create a VG. then create LVs that can stripe across all the 4 PVs. You can repeat the same for all the LUNs. But it is not so flexible as Veritas Volume Manager. And also you can define alternate pathing in LVM level.i.e. One LUN is assigned to two paths. This would be just active/passive configuration only. As long as you can use all the 4 controllers concurrently, that is fantastic. When the redundancy comes in to picture during a failure of any controller, anyway the performance would degrade to little extent.

Samir