Fibre Channel (SAN)

Reply
Contributor
Posts: 22
Registered: ‎08-20-2013
Accepted Solution

Split Fabric

Hello - I am new to the board and have what I hope is a fairly straight forward question for my first time.

 

I have one 2498-b40 SAN switch in my lab.  We bought two new ones.

 

Currently all host HBA's and SVC's run through the one switch.  We would clearly like to make this an A side and a B side.

 

Does anyone know of documentation on how to do this?  My first though was to do a cfgupload/cfgdownload to the new switches and just edit the zones.

 

Thoughts?

Regular Contributor
Posts: 161
Registered: ‎12-30-2009

Re: Split Fabric

That's indeed one way to reach you're goal.

Before you try it, I suggest you use SANHealth to get some insights in your current config.

 

Contributor
Posts: 22
Registered: ‎08-20-2013

Re: Split Fabric

Thank you for your reply.  I do run a SANHealth check every month.  It can't be that easy, are there any consideraations that I am missing?  I, obviously, have new IP addresses, domain ID's and names.  Is there anything I'm overlooking?

Regular Contributor
Posts: 161
Registered: ‎12-30-2009

Re: Split Fabric

Well from Switch POV it's not that difficult at all.

How it works with your SVC"s I don not know.

Some hosts (HPUX/AIX) dislike if their target ports (ie the switchport were their storage is) change.

In AIX you need dynamic tracking (i believe) and HPUX got a workaround since 11v3 called agile addressing.

 

If you have the licenses on your 3 switches to form a Fabric of 3 there's also another way to reach your goal.

 

-assign your new switches (soon Fabric A and B) a unique did/name/ip

-set the fabric wide parameters to match the old switch

-check if a firmware upgrade onthe OLD switch is needed/compatible

-ISL one new switch to the OLD one, it should merge

-ISL the other new switch to the OLD one, it should merge

-now start moving devices of you OLD switch to A&B, with one leg on A and one on B, if a host has more legs distribute them evenly accros A & B

-repeat until OLD switch is empty with the 2 ISL still present

-run SAN health

-remove ONE ISL from the old switch (segmenting the fabric in switch A and Old+B)

-If all is well you have two fabrics at this point, decom the OLD switch

-run SANHealth

-cleanup hanging members in both fabrics using SANHealth output

-done

Contributor
Posts: 22
Registered: ‎08-20-2013

Re: Split Fabric

Couple of rookie questions:

 

 

-set the fabric wide parameters to match the old switch - what exactly does this mean?

 

-ISL one new switch to the OLD one, it should merge

-ISL the other new switch to the OLD one, it should merge - Does this mean that I don't have to hand do the zoning?

 

Regular Contributor
Posts: 161
Registered: ‎12-30-2009

Re: Split Fabric

fabric wide parameters include tov like

configshow|grep fabric

fabric.ops.E_D_TOV:2000
fabric.ops.R_A_TOV:10000
Usually they are default across the switches.

So unless they have been changed in the past, you don't need to worry much.

Also the merge will faile with a reason should there be a mismatch in parameters.

 

A merge means the new switches will copy the zoning database from the old switch.

So in that sense you don't need to recreate your zones.

Although you should cleanup the hanging members once you have split the one fabric in two seperate fabrics.

 

The way to tackle this is all about knowledge, zoning size,timeline.

If the you have many zone and it needs to be done yesterday (like most things) you can do the merge than split way..

 

Contributor
Posts: 22
Registered: ‎08-20-2013

Re: Split Fabric

Are there any specific steps to decomming the old switch?   Or is it just a matter of turning it off?

Regular Contributor
Posts: 161
Registered: ‎12-30-2009

Re: Split Fabric

[ Edited ]

just disable the ISL ports to the new switched first, just to be on the safe side.

If each individual new switch keeps running just fine, you can sysshutdown the old switch.

 

If you need to clear the cfg due to security issues you can, after disabling the ISL ports, remove the ISL physical connections onthe old switch.

cfgclear clears all zoning info.

cfgsave saves the transaction.

Do not do this if you're new switches are still connected to your old switch.

 

Contributor
Posts: 22
Registered: ‎08-20-2013

Re: Split Fabric

[ Edited ]

I am begining to think that without any licenses I'm not going to be able to do this at all?  ISL is a licensed feature, yes?

 

Without any licensing any switch can only be a stand alone switch correct?

Regular Contributor
Posts: 161
Registered: ‎12-30-2009

Re: Split Fabric

Without some kind of fabric license you can not ISL to another switch, ie can only work in stand alone mode.

Perhaps this has changed in the years, as I only know of standalone, 2 switch fabric or full fabric licenses.

 

The question is what licenses has the box installed.

If you don't know by means of waybill, purchase order whatever, you need to follow the paper trail to know waht was ordered and what was delivered. Power up the new boxes to confirm if what was ordered was indeed deliverd.

Join the Community

Get quick and easy access to valuable resource designed to help you manage your Brocade Network.