problems adding 2 disks to ml350 g4 (SmartArray 641)

[Pier Maria]

Hi, I've got some problems adding 2 disks to my hp ml350 g4.

Original situation:
$ hpacucli ctrl all show config

Smart Array 641 in Slot 3 (sn: P92270P9SRL3DW)

array A (Parallel SCSI, Unused Space: 0 MB)

logicaldrive 1 (203.5 GB, RAID 5, OK)

physicaldrive 1:0 (port 1:id 0 , Parallel SCSI, 72.8 GB, OK)
physicaldrive 1:1 (port 1:id 1 , Parallel SCSI, 72.8 GB, OK)
physicaldrive 1:2 (port 1:id 2 , Parallel SCSI, 72.8 GB, OK)
physicaldrive 1:3 (port 1:id 3 , Parallel SCSI, 72.8 GB, OK)

I powered down the server, added 2 new disks ( same model/size )
and then rebooted...

ORCA show only the 4 original disks ( no spare/avaible disks)
and also hpacucli does not show new disks avaible to expand the
array called "A": the output of "hpacucli ctrl all show config" now
is still the same above...

Any Idea?

Thanks!

[Dmitry_75]

Hi! Look at back of scsi backplane. If backplane duplex version, it spited to 2 parts â 0-3 scsi id and 4-5 scsi id. In you case 1 channel RAID contr. you canâ t use duplex mode and must connect
too parts in chain

[Pier Maria]

How can I control if it's a duplex backplane?I can see only one flat cable from the controller board to another little board attached to the scsi backplane througt 2 ports...

To connect the 2 parts I need to use duplex mode?
How can I set up this option? ( I'm using Linux CentOS)

Sorry for all this questions, but it's my first scsi experience!
Thanks!

[Dmitry_75]

Please see attachment

[Pier Maria]

Ok thank you for the documentation.
I've just read that documentation but my ml350 seems to have something wrong:

I can see the duplex backplain, but it's only plugged by the bottom cable, the other one is missing. Is this the reason why the controller cannot see the 2 drives into bays number 4 and 5?

I need to buy the missing cable?
where it will be plugged?(I can see only one port on the "big scsi board", maybe there's a cable with two ports on one side[the backplane side] and only one on the other[the scsi board side]?)

Thank you

[Dmitry_75 · Accepted solution]

Yes, it is a reason.Connect scsi cable from
SA641 to UP connector, and plug in jumper cable to bottom and middle connector(remove terminator board if exist).Jumper cable you can make from standart 68pin wide ultra scsi cable by catting piece with 2 connectors.

[Pier Maria]

Ok that' s the solution using simplex mode, right?
This way I can merge the two busses and see all hard drives on the same channel. But will I degrade the server performances? This is a production server with many oracle istances installed...

In fact there's the little board that connects the 2 busses ports on the backplane (the middle and the bottom one), does it means the controller is using the first 4 drives in duplex mode or with only the bottom cable plugged is it in simplex mode?

If the actual first 4 disks are in duplex mode I need to mantain the actual configuration and maybe to buy the Duplex SCSI Backplain Option Kit to create a new raid1 array with the 5th and 6th disk.

Otherwise ( if actually the controller is in simplex mode ) I can buy only the jumper cable, remove the little board attached to the middle and the bottom ports of the backplain and connect them.

The last question: the server has a big board attached to the motherboard connected to the backplane as in the image of page 82 of your last attachment. At page 80 I can see the solution you posted, but in that image there's no "big scsi board"... why?

thank you