Need advice on disk mirroring

[Evelyn Daroga]

HPUX 11.00, N 9000 server; currently connected to a Xiotech san. We have a virtual disk configured which is mirrored at the san. The mirror is broken each night from the unix (commands issued to the san) for backup purposes, then rebuilt each day. The san is going away. Any recommendations on a product/method for duplicating this process? I beleive we are going to go to a locally attached SureStore array. Backup software is OpenView Data Protector A.05.10. Thanks in advance.

[Tim Nelson]

That would depend on the features and functionality of the SureStorage array you are looking at.

if this is a requirment then be sure the product you are buying has those features.

[Alzhy]

What IS stored on your Xiotech? An ORACLE DB or plain VxFS filesystems?

Your Options with an old (SCSI3?) SCSI Storage array could be:

1.) VxFS snapshots
2.) VxVM DJMR Option (software based approach of what your SAN can do)

Hope this helps.

[INH]

Hi,
Breaking mirror and remirror is the requirement? is Oracle database running ?

right now top of my mind is RMAN backup if itis supported Oracle DB.
As said in above replies check features are supported by product that you are buying

Regards,
INH

[Evelyn Daroga]

Thank you all for the replies.
We are planning to use an existing SureStore E-SC10 unit. It currently holds the boot disks (raided, but not sure at what level â how do I see that?). We are looking to add disks to hold user directories, other data/program files, and also Oracle 8.0.6 databases. While RMAN could be used for the databases (assuming that is available for Oracle 8), we also want to mirror some of the other filesystems. I have seen references to mirroring using logical volume manager, but that requires purchasing some DiskMirror software (I assume it is still available?). We are not using VxFS filesystems. At this point my choices would probably be, in the following order of preference: (1) mirror on the SC10, (2) mirror using LVM, (3) mirror using RMAN. Can anyone direct me to doc on how to do #1? I have found the user guide. That identifies mirroring as a feature, but doesnâ t show how to do it. If I have to go to #2, where do I find the software and the price? Thanks.

[Tim Nelson · Accepted solution]

Just looked through the E-SC10 manuall and this looks like a simple SCSI subsystem.

This product does not look like it has any raid/protection feature.

If I am right then the below would be the best configuration.

Two E-SC10 with matching number of disk.

use HPUX to LVM mirror the OS to two disk ( 1 from each subsystem)

use HPUX to LVM Distributed mirror on the remaining disk for DB and other software.

if you only have 1 E-SC10 then your HA and performance would not be as robust as 2. e.g. if the scsi bus or subsystem fails you are down. but you could then still LVM mirror two disks and LVM distributed mirror to the rest.

Mirror/UX is an add-on purchased/licensed production from HPUX. I do not recall if the 11.00 HPUX offered pre-bundled options.

"swlist |grep -i mirror" should show MirrowDisk/UX product.

[Evelyn Daroga]

Thank you, Tim. Your solution is what I would lean toward, if we do indeed use the E-SC10. We are exploring other options (e.g. iscsi interface to another storage unit) -- I may still use the lvol mgr for the mirroring (waiting for HP to give a quote on that). Thanks for the added detail of using a second E-SC10.

[Alzhy]

iSCSI and 11.0 OS?

I am not even aware iSCSI existed during the heydays of HP-UX 11.0.

Your N9000 server is old and will be getting pricey to maintain and upkeep.

Why don't you just recommend moving your HP-UX environment to a Linux/RHEL solution instead?

If it is a Database server -- the easier even.

[Evelyn Daroga]

Thanks, Alzhy, for the reply. There are numerous reasons why we are still on HPUX 11.0, and we are in fact in the process of migrating to an SAP solution. In the meantime, I still have to address this issue. I donâ t know if 11.0 can utilize iscsi â thatâ s why Iâ m exploring it (I did find a Cicso iscsi driver for HPUX 11.0).

[Alzhy]

Well -- your best bet right now is to "scrounge" for additional USCSI HBAs and SCSI DIsk enclosures Ma'm so you can match the performance of your Xiotech array.

There should be a lot on the "gray market" these days for cheap. Lots of DS21XX enclosures even that may fit the bill or even non-HP SCSI enlosures.

Planned properly in LVM (ie. Striping, RAID10, hot spares and LVM mirroring/snapshots - you can have your 11.0 environment restore its glory as if the Xiotech never left)

Good luck.