EVA4000 moving EMU cable on-line

[jpmartin]

Hi,

is it possible to move on-line EMU cable on an EVA 4000 storage array.

The reason is to add a third shelve on bottom, but the free EMU connection is on top, and the idea is to move up the three EMU connections (Y cable and two single cables).

Thank you for help

[jpmartin]

The configuration from top to bottom is :

- free connection on EMU ID#4
- HSV200's on EMU ID#3
- first enclosure on EMU ID#2
- second enclosure on EMU ID#1

So, the right question is :

is it possible to disconnect the Y cable on EMU ID#3, then plugg on EMU ID#4 without disruption ?

[gregersenj · Accepted solution]

No.

Controller pair must! have ID 3.

HDD shelf 3 and 4 should have ID 5 and 6.

Don't mess with the CAB on a running EVA. If you have to make changes on the CAB, shut down the EVA.

[jpmartin]

Thank you for the response, it is not possible to mess with the CAB on-line.

So, i a have already configured some EVA4000 wih HSV200 Controllers on ID#5, and disks enclosures above with ID#4, ID#3, ID#2 and ID#1, and it is running fine.

[Uwe Zessin]

Well, it seems that the people at HP cannot decide how to configure an EVA and change the 'rules' from time to time:

A customer has forwarded me the following instruction he received in January from HP support:
> 3. It is also noticed that the enclosure numbering in this array is
> not as per the HP recommendations. Please rearrange the EAB
> connectors so that the controller enclosure has enclosure ID 5.

This was for a 4100. I have several revisions of the 'public' EVA disk placement guidelines and in the first ones it was #3 on the 4000/4100, in newer ones it is #5 and the "Hardware Configuration Guide" which at least has an official document number says:
""NOTE:
The configurations described in this guide are the preferred configurations. Other configurations may be used, but ensure that enclosure ID 7 is not used for any disk enclosure.""

If you look at the pictures you see that there are 1, 2, 3 or 4 disk enclosures with the controller enclosure immediately on top and connected to the next free EAB address (2,3,4,5).

[jpmartin]

Yes, with the Hardware Configuration Guide 5th edition February 2008 on Chapter 4

http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c01364500/c01364500.pdf

the HSV200 Controllers ID number is changing according the EVA4000/4100 model:

2C1D is ID#2
2C2D is ID#3
2C3D is ID#4
2C4D is ID#5

If it is not possible to mess with the CAB bus on-line, that means there is a single possibility to add on-line an enclosure on 2C1D model with above configuration:

with ID#3

[gregersenj]

hmm. might be my disk placement guide is a bit old.

If you you need to add more EAB cables, you have to remove the terminator, and that mean shut down the EVA.

For as long as you got free connectors on the EAB, you can hot add enclosures.

[jpmartin]

No, in the past, i have already added a EAB cable on-line to add an enclosure without priblem,

but i have never played with disconnecting/reconnecting the HSV200 Controllers cable

[Sebastián Graña]

Hi,

I had upgraded an EVA4100 online from 2C1D to 2C2D, and also had moved the Y cable online with no problems, from position 2 to position 3.

It is not clear in the enclosure installation guide, but I was told by HP that is possible to do this change online.

Regards

[Uwe Zessin]

> had moved the Y cable online with no problems

Maybe you have been lucky. One of my customers had to reboot at least one of their 4100 controllers, because they were no longer visible after the HP tech. had moved them to ID:5 as instructed by the call center.

Well, maybe my customer was unlucky, but such a reboot (even if it is semi-transparent to the hosts) does not count as an "online change" in my book.