VA7400 Controller replacement

[Lawrence Kaufman]

My ongoing project has been setting up two VA7400 disk arrays in a SAN. I submitted a couple of questions in the past few weeks and you guys put me on the right track- Thanks all. However, my latest issue is that I had a bad controller. The HP CE replaced it...and it seemed to work OK. However, the N_port ID/WWN for that new controller is different and it created new device files. Now, I have to export and import VGs again. The CE told me that if I did not have a fibre switch it would have retained the same instance number on the device files.
My question is: Is there an easier way to replace a VA controller in a SAN environment?

[Torsten.]

If you exchange a controller this part will have a new WWN, but the device files for all the LUNs should not change.

Because of the changed WWN the "fcmsutil ... replace_dsk ..." command or a server reboot is needed to make the new controller accessible.

You wiull see related messages in your syslog file.

[Lawrence Kaufman]

I tried the fcmsutil /dev/tdx replace_dsk command. I did not have any luck. I must have done something wrong. I used the "display all" command to get the N_port ID. The man page was not a lot of help.

[Crewescontrol]

Hi Lawrence,

As Torsten says, check your syslog or dmesg for the relevant message and N Port ID. See the attached which i put together a while ago for a colleague.

Please note, for fcmsutil replace_dsk to be the answer to your problem, you should be seeing NO_HW in tdlist / ioscan for the controller. If it has actually changed your device files i think it could be another issue.

Cheers

[Lawrence Kaufman]

Thanks! I read the document and I am going to give it another shot tonight. I will report tomorrow.

[Torsten.]

Be aware "fcmsutil ... replace_dsk" is only needed if a WWN is changed while the nPort ID stays the same and there is no reboot for the server. If you reboot the server, the effect is the same.

this only affects the driver and the device authentication.

Can you confirm you have new device files now?