topic Migrating to new switches in HPE EVA Storage

Migrating to new switches

Joseph Borgia — Tue, 08 Jul 2008 19:58:13 GMT

I have a fairly simple configuration: 2 fabrics of 2 switches each, all 2Gb. I'm ready to migrate to my new 4Gb switches. What I was wondering was, can I migrate one fabric at a time? Will there be a problem with one fabric running at 2Gb while the other runs at 4Gb during the migration? All systems are dual connected.

Re: Migrating to new switches

IBaltay — Wed, 09 Jul 2008 04:07:46 GMT

Hi,

Introduction

It is good to do only one fabric at a time, in other words, the first week fabric Nr. 1, the second week fabric Nr. 2 to have one week of production of the new fabric in between to be able to evaluate if everything works fine in a sufficient/reliable time frame.

Reusing of the existing zones

No matter if you are using the port zoning or the port wwn zoning, you can choose the scenario of adding a new switch to the existing fabric for the trick to reuse the existing zones

Preparation steps:

disable the 1stNewSwitch (switchdisable, configure->switch fabric settings ->unique id, identical PID format, ...etc.
For the ISL link to the original switches you need to temporarily set the port speed to the 2Gb (portCfgSpeed) and cable it to it.

Enabling the switch:

Then you can enable the 1stNewSwitch and if everything is ok, the new switch will enter the fabric and get all zonning information.
Now you should direct all the appropriate hosts to communicate via the fabric which you did not touch.

Changing the domain ID to the original (powered off switch):

then you can turn of one of the original switches. recable the hosts into the new switch exactly the same as it was in the original switch. Switch disable the new switch and change its domain id to the original switch (reuse the zones of the original switch)

Check:
Then check the new host connections from the appropriate hosts.

If everything works fine
Repeat all steps also for the 2nd new switch

Note:
Dont forget to reconfigure the ISL port of the 1stNewSwitch (portCfgSpeed to 4Gb) and connect it with the same port of the 2ndNewSwitch.

At the end check all host connections of the new fabric and then you have one week in between to check the stability of the new fabric

Re: Migrating to new switches

Frank_W — Wed, 09 Jul 2008 08:48:11 GMT

Hi,

It doesnt matter for the server if the fabric runs with 2 ore 4 GBit.

What operating systems are in use?

When you are using HP-UX, the devicefile of the disks will depend from the domain-ID of the switch and the "port-ID" of the switch-port where the storage-system is connected. If these change, you will get new device-files and you will have to vgexport / vgimport your volumegroups.

Whith Windows and Linux, it doesnt matter

Re: Migrating to new switches

Joseph Borgia — Wed, 09 Jul 2008 14:44:16 GMT

When you say "Now you should direct all the appropriate hosts to communicate via the fabric which you did not touch.", do you mean go into CVEVA to the vdisk presentation tab for the host and change the preferred path/mode from "no preference" to the A or B path?

Since I'm dual connected, couldn't I just do this hot anyway since downed fabric I'm working on should just fail-over?

I guess I'm trying to figure out where I'd direct my hosts to the other fabric while I'm working on the first one.

Re: Migrating to new switches

IBaltay — Wed, 09 Jul 2008 14:46:09 GMT

Hi, you should do it on a host side via the multipath driver options