ssa disks: fast write cache

[ogniemi]

Hi,

Configuration is:

* 2 LPARS AIX 5.2_ML02,
* each LPAR has 2 x "IBM SSA 160 SerialRAID Adapter (14109100)" with
* 2 SSA loops - each goes via 1 SSA adapter in each of system (so each loop has 2 SSA adapters and 8 new SSA160 Physical Disk Drive (72800 MB))


# lscfg -vl ssa0|grep Z1
Device Specific.(Z1)........CACHE=32
# lscfg -vl ssa1|grep Z1
Device Specific.(Z1)........CACHE=32

# ssa_fw_status -a ssa0 -c
Active
# ssa_fw_status -a ssa1 -c
Active


When I run command
smitty ssafastw

I get following error:
1800-051 There are no items of this type.


Could anyone please tell me what is reason of this error?


regards, m.

 

[TJmike]

Hi there,

That config is not valid.
here are some details of it.

Specs:
AIX: 4.2.1, 4.3.0
8 initiators Non-RAID / 2 initiators RAID-5
From 3 to 16 drives per RAID Array.
Bus width: 32
Busmaster: Yes
Adapter Type: Long
Data transfer rate: 20MB/40MB SSA link speed automatically negociated
Loops: 2
Max disks/loop: 48
Adapter Compatibility: 4M, 4N and 4P (Note 1)

RAID support: RAID 0, RAID 5 Fast-Write Cache and Non-RAID Single Adapter - RAID 5 with Fast/Write cache.
Single Adapter - RAID 0. Two Adapters - RAID 5 and Non Fast/Write. Hot Spare: Yes
Fast Write Cache Option: 32MB
RAID/Spares Span Loops: No.
Boot Support: Yes
Dump tool: Requires Hot Spare

Note 1) Two adapters per loop with RAID and non Fast Write Cache,Eight adapters per loop non-RAID and non Fast Write Cach.

But check the label of your adapter microcode, if it's below 5000, try to upgarde to 8300. this is a new release microcode. this might work on your desired config.


regards,
TJmike

 

[ogniemi]

Please explain more detaily:

each of my loops has only 2 adapters (different adapters)

# lscfg -vl ssa0
ssa0 U1.9-P2-I1/Q1 IBM SSA 160 SerialRAID Adapter (14109100)

Part Number................. 09L5695
FRU Number.................. 34L5388
Serial Number...............S2333452
EC Level.................... E27782
Manufacturer................IBM053
ROS Level and ID............C400 0000
Loadable Microcode Level....05
Device Driver Level.........00
Displayable Message.........SSA-ADAPTER
Device Specific.(Z0)........SDRAM=064
Device Specific.(Z1)........CACHE=32
Device Specific.(Z2)........UID=006094C100005D16
Device Specific.(YL)........U1.9-P2-I1/Q1


Why FWC cannot be enabled?

regards, m.

 

[TJmike]

check on the RAID SUPPORT.

*Two Adapters - RAID 5 and Non Fast/Write.

this means that you cannot use the F/W cache when you use two cards in one loop. You can use the F/W when you use one card for a RAID config. But theres a new microcode that you can load to the adapter. Try lo load it first, this might be the correction on the first limitation of the card. I'm not yet sure if it's already available on the web. try to contact IBM. But as for your current setting, it's not supported.

TJmike

 

[ogniemi]

I enabled fast FWC. It works on two loops each one having 2 SSA Adapters. (I wouldn't use FWC when I had more then 2 advanced adapters in loop but I have only 2 in each loop).

Problem was caused by logical disk names!!!!!! Yes, I had "-" in logical disk names (ssaR4D7-11, ssaR4D7-12....) and was a problem during FWC enabling.


regards,
m.