Integrity Servers
cancel
Showing results for 
Search instead for 
Did you mean: 

Two disk drives attached to the same SCSI interface card on RX4640

 
SOLVED
Go to solution
CAS_2
Valued Contributor

Two disk drives attached to the same SCSI interface card on RX4640

Hi.

Due to some performance problems in a rx4640 IA64 server, I discovered that both disks in VG00 attached to the same SCSI interface card:

Class I H/W Path Driver S/W State H/W Type Description
============================================================================
disk 0 0/0/3/0.0.0.0 sdisk CLAIMED DEVICE TEAC DV-28E-B
disk 1 0/1/1/0.0.0 sdisk CLAIMED DEVICE HP 36.4GST336753LC
disk 2 0/1/1/0.1.0 sdisk CLAIMED DEVICE HP 36.4GST336753LC

In the other hand I found two SCSI interface cards:

ext_bus 2 0/1/1/0 c8xx CLAIMED INTERFACE SCSI C1010 Ultra160 Wide LVD A6829-60101
ext_bus 3 0/1/1/1 c8xx CLAIMED INTERFACE SCSI C1010 Ultra160 Wide LVD A6829-60101

First, I thought HP staff didn't configure properly this server and they inserted both disks in two slots attached to the same If Card -- I guessed this server had 4 slots for disks as L-class server had.
Due that I cannot see the box, I downloaded Rx4640 operations manual from HP doc site and saw that ONLY two internal disks are possible.

Then, Why both disks are attached to the same SCSI interface card and other one has no device attached ?
8 REPLIES 8
Torsten.
Acclaimed Contributor
Solution

Re: Two disk drives attached to the same SCSI interface card on RX4640

While ordering the system, you can order it with or without the dual bus (duplex) option.

The default is a single bus configuration, so both disks are on only one bus.

Same for rp4440.

If in simplex mode, you may use the upper of the 2 external connectors. In duplex mode non of the external connectors is supported.

Hope this helps!
Regards
Torsten.

__________________________________________________
There are only 10 types of people in the world -
those who understand binary, and those who don't.

__________________________________________________
No support by private messages. Please ask the forum!

If you feel this was helpful please click the KUDOS! thumb below!   
timmy b.
Honored Contributor

Re: Two disk drives attached to the same SCSI interface card on RX4640

CAS,

Torsten is (as usual!) correct. You need to have the duplex option to put your drives on individual busses. Here is the link to the installation manual, look to page 61 or so for the Duplex board instructions. This manual is VERY handy, with a lot of good information.

http://tinyurl.com/cyrh8

Good Luck - Tim
There are 10 kinds of people in this world: Those who understand Binary, and those who don't.
Zygmunt Krawczyk
Honored Contributor

Re: Two disk drives attached to the same SCSI interface card on RX4640

To convert from simplex to duplex SCSI you need to buy duplex PCA backplane A9740B
rick jones
Honored Contributor

Re: Two disk drives attached to the same SCSI interface card on RX4640

And, with the "how to get the two internal discs on separate SCSI busses" question addressed, what sort of performance problem were you having and what leads you to suspect the issue is with having both discs on the same SCSI bus?
there is no rest for the wicked yet the virtuous have no pillows
Torsten.
Acclaimed Contributor

Re: Two disk drives attached to the same SCSI interface card on RX4640

@timmy: Thank you! ;-))

Regarding Ricks posting: Do you have any problem with this configuration? Even you have the duplex config, there are still SPOFs like the I/O card and the slot.
No reason to be worry about the config.
A single server isn't a high availability environment, but your current performance should be good enough.

Hope this helps!
Regards
Torsten.

__________________________________________________
There are only 10 types of people in the world -
those who understand binary, and those who don't.

__________________________________________________
No support by private messages. Please ask the forum!

If you feel this was helpful please click the KUDOS! thumb below!