topic Re: if is possible in Operating System - HP-UX

if is possible

Slawek Ksiazek — Wed, 04 Mar 2009 12:28:01 GMT

I have question

if is possible create on HPUX about ~500 or artificial/fake disks devies?I need prepare to test system with 500 or more disks, but I havn't enough luns on storage systems.Thanks a lot for help.

Slawek

Re: if is possible

TTr — Wed, 04 Mar 2009 13:48:58 GMT

You can create the device files with the "mknod" command but you cannot use these in LVM to create volume groups and logical volumes. I know of now way to actually present fake disks and use them for LVM. Unless there is something like this in the intergrity virtual machine environment, similar to what VMware is doing.

Re: if is possible

Srimalik — Wed, 04 Mar 2009 14:54:36 GMT

There was facility to setup loopback devices in earlier releases of HP-UX but now it is not there :-(.
I really miss losetup(linux)/lofiadm(sol) on HP sometimes.

Re: if is possible

VK2COT — Thu, 05 Mar 2009 02:16:51 GMT

Hello,

Loopback file systems are still supported
and available (even in HP-UX 11.31).

Example:

# mount -F lofs /usr/sbin /tmp/sbin

More details in mount_lofs(1M).

This creates "additional" file systems but not
LUNs or physical volumes, so LOFS is not going
to help you.

If you want to do some load testing, refer to
several other references in this forum that
discuss various tools for it (some free
and some commercial).

Cheers,

VK2COT

Re: if is possible

Slawek Ksiazek — Thu, 05 Mar 2009 05:45:33 GMT

Thanks all for help,but still i seek solution where i can create fake disks devices.I need only it discover trough ioscan.

Best

Sk

Re: if is possible

Srimalik — Thu, 05 Mar 2009 06:13:20 GMT

>mount -F lofs /usr/sbin /tmp/sbin
it is more similar to the --bind option available in linux. But there seem to be nothing like losetup.

you can use losetup to make files(usually sparse files with very large holes) appear as block devices in /dev/ which can be used by LVM.

Re: if is possible

Armin Kunaschik — Thu, 05 Mar 2009 12:48:36 GMT

If you have 11.23 or 11.31 you can use iSCSI. Use another box to create many small "LUN's" and present it to your box.

My 2 cents,
Armin

Re: if is possible

Slawek Ksiazek — Fri, 06 Mar 2009 05:42:05 GMT

How can I use iscsi to do it? How looks like configuration iscsi on HP?Thanks for info.

Slawek

Re: if is possible

TTr — Fri, 06 Mar 2009 12:51:48 GMT

> Use another box to create many small "LUN's" and present it to your box.

You still need a iSCSI storage server for this. The HP-UX iSCSI software is available only in initiator mode and NOT in target mode. At least I have not seen any iSCSI software to allow iSCSI target configuration in HP-UX.

http://docs.hp.com/en/T1452-90011/T1452-90011.pdf

Re: if is possible

TTr — Fri, 06 Mar 2009 12:56:44 GMT

I think you need to invest on some hardware here to provide the disks to your server. Even a small RAID card with 1-3 disks would be sufficient. But you should check the RAID card, they have a limit on the maximum number of LUNs you can create in them.

What exactly are you trying to do with that many LUNs on your server?

Re: if is possible

Armin Kunaschik — Fri, 06 Mar 2009 13:03:03 GMT

There are many possibilities... check your favourite OS for iSCSI target support. Current Windows and Linux versions should be able to present iSCSI-LUN's. Netapp Filers are able to present iSCSI LUN's... also some EMC or HP boxes.

My 2 cents,
Armin