topic Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling in MSA Storage

Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

swazilee — Tue, 17 Jan 2012 07:29:32 GMT

Hi,

I have inherited an EVA 6000 that was upgraded from a 2C4D to a 2C8D and ID Port 5 and 7 were used for the new drive enclosures when the Enclosure Address Bus (EAB) Cabling was done. ID Port 9 was used for the controllers. It seems to be working but I understand that this is incorrect and an unsupported config. I have some maintenance to do on the system soon and was wondering what impact changing the EAB cabling to the correct config would have on my data? Would I lose data because the Drive Enclosures would be on a different port after the change?

Thanks

Lee.

Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

Sebastian.Koehler — Wed, 18 Jan 2012 20:02:51 GMT

Don't worry. I had to do this one or two times. Just shutdown the array and turn of the shelfs as well. Correct the cables, turn on the shelfs and verify EAB addresses first. Turn on the controllers if the addresses are as expected. The system will find all the drives, metadata and start the system without any issues. Are you aware of the IDs that should be used?

Regards,
Sebastian

Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

swazilee — Thu, 19 Jan 2012 12:23:34 GMT

Thanks for the reply Sebastian.

As i understand it, ID 5 and 7 should not be used, they supposed to be for the controllers. So in my case the first 4 enclosures will keep there ID's, the top 4 will change there ID's.

And hopefully restores wont be required. ;-)

Thanks again.

Regards

Lee.

Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

Sebastian.Koehler — Thu, 19 Jan 2012 12:39:27 GMT

I've attached a picture for your reference. Use ID 5 for the controllers and do not use ID 7.

Regards,

Sebastian

Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

swazilee — Thu, 19 Jan 2012 13:18:23 GMT

Very helpful.
Thanks.

Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

swazilee — Thu, 19 Jan 2012 13:22:21 GMT

By the way, any idea what terrible things are supposed to happen if you use ID 5 and 7. This EVA had enclosures on 5 and 7 and seemed to be running ok?

Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

Sebastian.Koehler — Thu, 19 Jan 2012 13:35:15 GMT

Based on the ID of an enclosure AL_PAs are assigned to devices. This is true for the controllers and drives. ID 7 causes the highest available AL_PAs to be assigned to the attached devices. To ensure the controller is able to remove misbehaving drives from the loop, they need to have the highest AL_PA on the backend loop. As long there is no faulty drive in the EVA, you will not see any negative effect.

Regards,
Sebastian

Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

swazilee — Thu, 19 Jan 2012 14:40:59 GMT

Thanks for your time.

Re: Correcting EVA6000 Enclosure Address Bus (EAB) Cabling

Sebastian.Koehler — Thu, 19 Jan 2012 15:39:44 GMT

You're welcome. Don't forget to assign a kudo or two. :)