MSA 1000 - Connection Profiles ???

[Stephen McKay_3]

I've been reading though a documents called "Using HP’s MSA1000 with 2.4-based Linux distributions on HP Servers" and com accress the following:
"
When initially powered on, the MSA1000 will detect HBA connections and assign them a default profile of Default. This profile must be changed to Linux using the “ADD CONNECTION” command..."

Can someone please explain what the connection profile does? The options seem to include Windows Linux & NetWare, and "Default".

I need to know what the "Default" profile is, and what effect the profile has on the client system. For instance, if a Linux server has been using a DEFAULT connection profile, instead of a the "Linux" prfile, what is the effect - is it purely performance, or are there implications for data integrity? Does it make any difference what the filesystem being accessed is, (i.e. EXT3FS vs REISERFS)?

If anyone can shed some light on this it would be appreciated.

Regs

[Uwe Zessin]

A wrong connection profile can have a disasterous effect on the server - I've heard about a big AlphaServer GS140 with a big SAP R/3 instance crashing due to a wrong setup (wasn't connected to an MSA1000, but other storage arrays have similar mechanisms ;-).

It has nothing to do with the file system, but with the low level SCSI protocol handling. Unfortunately, different operating systems have different requirements that need to be accomodated by the storage array...

[Bob_Vance]

You can do a 'show profile' to dump a profile.

Here' some notes I made a while back:



DaytonaMSA> show profile hp
Profile name = HP
... Mode 0 = Volume Set Addressing
... Mode 1 = Asymmetric Failover
... Mode 2 = Logical volumes connect as available on Backup Controller
... Mode 3 = Product ID of 'MSA1000 VOLUME'
... Mode 4 = Normal bad block handling
... Mode 5 = Logout all initiators on TPRLO
... Mode 6 = Fault management events not reported through Unit Attention
... Mode 7 = Send FCP response info with SCSI status
... Mode 8 = Do not send Unit Attention on failover
... Mode 9 = SCSI inquiry revision field contains the actual version
... Mode 10 = SCSI inquiry vendor field contains Compaq
... Mode 11 = reserved
... Mode 12 = Enforce Force Unit Access on Write

DaytonaMSA> show profile Linux
Profile name = Linux
... Mode 0 = Peripheral Device LUN Addressing
all others = HP

DaytonaMSA> show profile default
Profile name = default
... Mode 0 = Peripheral Device LUN Addressing
... Mode 1 = Legacy Failover
... Mode 5 = Logout selected initiators on TPRLO
... Mode 7 = Do not send FCP response info with SCSI status
... Mode 8 = Do not send Unit Attention on failover
... Mode 12 = Ignore Force Unit Access on Write
all others = HP


Just from the description of the mode differences, it would appear that you do not want the default. But what they all actually mean, I do not know.

I do know that PDLA (Peripheral Device LUN Addressing) makes the MSA present the LUN one number higher to the host. I.e., MSA_LUN0 is presented as LUN 1 on the bus.

I used the "hp" on my MSA-rx1600(Integrity) connections, because I was dual booting HPUX and Linux and I didn't want any possible issue with LUN0. A side effect of this was that HPUX could only see 8 LUNs (actually, 1-7 because 0 shows up as a ctl device, not a disk), so I dedicated the lowest ones (1-5) for the HPUX boot and the rest for the Linux boot.


hth
bv

[Bob_Vance]

Oooops.
I meant to say that I set them all to Linux !!!!!
Thus MSA LUN0 = LUN1 = /dev/dsk/cXtTd1 .
/dev/dsk/cXtTd0 is reported as a ctl device and is not used.


bv