12H Configuration on L1000

[James Longfield]

Can someone give me an example on how to create LUNS in a 12H DISK ARRAY using command line ?

[S.K. Chan · Accepted solution]

See my answer in this thread ..
http://forums.itrc.hp.com/cm/QuestionAnswer/0,,0xdc7842308663d611abdb0090277a778c,00.html
Hope it helps ..

[James Longfield]

In the creation of the volume group in your example you had created VG01 with a primary and secondary path I suppose. How do you know which device path to use ?

[S.K. Chan]

After you have created your luns in the 12H you would run ..
# ioscan -fnC disk
and from the newly created device files as a result from your luns, you can kind of fgure out which is which. If you got a "dual-channel" setup you should see them appearing in pairs. For example ..
c4t1d0 - pri
c5t2d0 - scondry
This is a pair.
c4t1d1 - scondry
c5t2d1 - pri
This is a pair.
The only thing similar in the above pairs are the luns id ie (0 and 1). It's up to you which one you would choose as your pri and which one as secondary. I suggest you alternate them, like the example above.

[Eugeny Brychkov]

Excellent posts. I would only add:
1. 'ioscan' scans for devices. Device files should be creted then manually using 'insf -e' command;
2. how to use primary and alternate paths (controllers X and Y) is to load balance I/Os between them (paths and thus controllers). You should have an idea about how much your data on LUNs is accessed, and then split access (I/Os) between two paths. Simplest, if you suspect all LUNs are accessed equally is to split all LUNs in two groups of equal number of LUNs and access one group LUNs through X and another through Y
Eugeny

[James Longfield]

Thanks to all ! One last question, it there a way to not having to use the array ID in the command line. What I mean is are there any other way to identify the 12H not by using the array ID ?

[S.K. Chan]

Not sure what you mean, I can only guess .. what you can do is set the alias on the 12H, that would make it easy for you. Take for example ..
# arraydsp -i
Array with S/N: 000000062F32
If you do ..
# man arraymgr
.. and take a look at option "-D" to set the alias. So you can run ..
# arraymgr -D MY12H 000000062F32
==> this set the alias to "MY12H"
# arraydsp -i
Array with S/N: 000000062F32 Alias: MY12H
And going forward you can use the alias name to call the array (ie you don;t need to remember or query the array id). Example ..
# arraydsp -a MY12H
would be similar to ..
# arraydsp -a 000000062F32