Finding cXtXdX

[Chris Fadrowski]

What is the best way to find the cXtXdX number of an HBA that is not presently connected to disk? is there a way to do this?

I have two HBA's in an Itanium server running 11.23 v2, and would like to do some pre-wiring and labeling for a new SAN.

[Torsten.]

The ioscan -fn output will show the hardware path and if you tell us what server you are using, we can tell you the slot.

another method is "olrad -q"

[Bharat Katkar]

HI,
Looking at the Hardware path of the HBA controllers you can easily make out in which slot they are in.

Use "ioscan -fnC ext_bus"
This will display all the adapters installed into your system.

Regards,

[Chris Fadrowski]

Class I H/W Path Driver S/W State H/W Type Description
=================================================================
fc 0 0/3/1/0 td CLAIMED INTERFACE HP Tachyon XL2 Fibre Channel Mass Storage Adapter
/dev/td0
fc 1 0/3/2/0 td CLAIMED INTERFACE HP Tachyon XL2 Fibre Channel Mass Storage Adapter
/dev/td1

rx4640

[Torsten.]

Sorry, I missed something (cXtXdX number, of cause). But the ioscan is the key, because it depends on the instance number.

[Chris Fadrowski]

Slot Path Bus Max Spd Pwr Occu Susp OLAR OLD Max Mode
Num Spd Mode
3 0/3/1 128 66 N/A On Yes No Yes N/A PCI-X PCI
4 0/3/2 128 66 N/A On Yes No Yes N/A PCI-X PCI
5 0/4/1 160 66 N/A On Yes No Yes N/A PCI-X PCI
6 0/4/2 160 66 N/A On Yes No Yes N/A PCI-X PCI
7 0/2/1 64 133 133 Off No N/A N/A N/A PCI-X PCI-X
8 0/5/1 192 133 133 Off No N/A N/A N/A PCI-X PCI-X

looks like it is in slots 3 & 4, how do you trace this back to cXtxDx

[Bharat Katkar]

Yes ...
Now disk connected to HBA at slot 3 will inherit HW path 0/3/1 and further continue to incicate the instance/target/lun no.

Something like 0/3/1.x.y.z

Regards,

[Chris Fadrowski]

so c3tXdX and c4tXdX?

[A. Clay Stephenson]

Sorry, it's not that easy. It depends upon the order in which the hardware is "discovered". You can't automatically assume that because a controller is inserted into slot X, for example, that it gets controller instance Y. This is intentional so that when new hardware is introduced the old instance numbers are preserved. When new devices are added to an existing box then the lowest slot number (lowest hardware path) gets the first available new instance number.

[Chris Fadrowski]

so then there really isn't a way to determine what the cxtxdx is until i connect it up.

[Torsten.]

Please give us an output of

ioscan -FnH0/3/1/0

and

ioscan -FnH0/3/2/0

[Bharat Katkar]

yes ...exactly.
Regards,

[Bharat Katkar · Accepted solution]

so then there really isn't a way to determine what the cxtxdx is until i connect it up.!!
Yes .. you are correct.
From cxtxdx cx instance no is alloted by System and tx is target i.e. SCSI ID and dx is LUN no.

[A. Clay Stephenson]

No, it's predictible but it's simply not a direct mapping of slot numbers to instance numbers. Consider the case where you intentionally installed a controller in the slot with the highest path -- let's say that it gets instance '1'. You would not want c1 to suddenly become c2 when you install another SCSI controller in a lower numbered slot.

Essentially, your lowest free hardware path will be assigned the next instance number.
You do have the option of using ioinit to coerce the process and force your own assignments on the system BUT do so with care.

[Chris Fadrowski]

>ioscan -FnH 0/3/1/0
pci:fcms:F:T:F:-1:61:4294967295:fc:td:0/3/1/0:16 60 16 41 0 0 0 0 :0:root.sba.lba.td:td:CLAIMED:INTERFACE:HP T
achyon XL2 Fibre Channel Mass Storage Adapter:0
/dev/td0
root@hostname:/>ioscan -FnH 0/3/2/0
pci:fcms:F:T:F:-1:61:4294967295:fc:td:0/3/2/0:16 60 16 41 0 91 196 0 :1:root.sba.lba.td:td:CLAIMED:INTERFACE:H
P Tachyon XL2 Fibre Channel Mass Storage Adapter:1
/dev/td1

[Torsten.]

I didn't get your question in the beginning, sorry.

Let's say cxtydz.

I'm pretty sure we can find out the "cx" portion in the device file, but the "tydz" depends on your SAN devices. Without knowing the device and the device configuration, nobody can tell you the exact device files.

[Chris Fadrowski]

actually, i am just looking for the "cX" number.

[Torsten.]

This won't give any *useful* information for you. Imagine you know the first "cx" for the first FC HBA. Depending on your SAN there will be a lot of devices behind /dev/td0, including cx+1tydz, cx+2tydz, cx+3tydz... so it is impossible to say at this time with the information provided, what will be behind /dev/td1, the second FC HBA.