6509 - 6513 Migration - Need help :)

dclee · ‎01-10-2012

Looking for a bit of design help

We currently run 1 Cisco 6509 (CatOS) for our production network. It has multiple vlans which feed distribution switches on each floor in 2 buildings.

Essentially each floor is its own vlan. Each floor switch is connected back to the 6509 via fiber connections.

We also have several production vlans that our VMware and AIX environments connect to.

I would like to phase out the the 6509 and replace it with a new 6513 chassis, sup720's etc. Currently it is sitting next to the 6509 in the rack.

I need to limit downtime as much as possible but can get one shutdown window over a weekend. However I dont think it would be enough time

to move all of the existing etherconnections etc etc

So I am looking to run them both at the same time and slowly migrate over to the 6513 over the next few months.

My solution was to use the 6513 (IOS) in L2 mode only for now and trunk it back to the 6509 via 4 1 gig connections in a LACP config.

So the 6509 would still be handling all of the L3 routing for now.

Once I had moved all of the fiber and ethernet connections over to the 6513, I would use the shutdown weekend to configure the 6513 for L3

and essentially turn off the 6509 at that point.

My questions are

- Is there a better way to do this ?

- By trunking the 6513 to the 6509 do I need to worry about any loop issues ?

- I am aware of the oversubscription issue for the port channel and have spread the 4 interfaces over the different groups of asics.

Any help would be appreciated.

Cheers

Dave

sleepyshark · ‎01-10-2012

define "limit downtime".....

In this particular situation going from CatOS to IOS, i'd keep the 6500's seperate and duplicate configs between, build the core network, VLANs and routing, then do a heavy-lift later-night'er and move links from 6509 to 6513.

This suggestion would keep your uptime as high as possible during the config process and allow you to test until you're confident you're ready to swap. The physical process to move a link from one chassis to another shouldn't take more than a few seconds to complete.

Thanks,

Sean Brown

http://www.sleepyshark.com

dclee · ‎01-10-2012

Well I have 5 6548 line cards that are pretty much full with ethernet connections. All production connections to vmware or AiX environments.

On top of that there are multiple etherchannels connecting into the vmware and Aix environments.

I also have 2 6408 cards that are full, which are the connections to each of the floors in both buildings.

So best case I would be able to start early Sat morning once backups were finished and then work to get all of these connections recabled and tested to the new 6513..and have everything back online by 5pm Sun eve.

Just doesnt give me alot of buffer room if there are any problems.

Which is why I thought if I could trunk the 2 of them together I could slowly move the physical connections over and then make the L3 cutover when that was finished.

Cheers

Dave

Leo Laohoo · ‎01-10-2012

Well I have 5 6548 line cards that are pretty much full with ethernet connections.

Full of what??? The 6548 is NOT designed to be used in a data centre. It's designed as an access switch (thus a PoE option is available). SO what happens when you have a 6548 stuffed with DC servers? You'll get packet drops.

A DC line card for the 6500 is no other than the 6748 (Table 4).

Cisco Catalyst 6500 Series 10/100- & 10/100/1000-MBPS Ethernet Interface Modules

dclee · ‎01-10-2012

I appreciate you being candid...lol and I am well aware the 6548 uses and features...Which is why the 6513 has 6748's cards in it

Which is also why I am trying to phase out the 6509

Now back to the actual migration, do you see any issue with me using the port channel trunk between them to get this migration moving along ?

Cheers

Dave

Leo Laohoo · ‎01-10-2012

Etherchannel against an AIX or other VMwares can sometimes be a hit-and-miss. We did something like this several times and in several weekends. First two times, the AIX and/or VMware guys/gals were at home and VPN in and it was frustrating because they keep saying it's a "network issue" and hang up the phone.

The next few times we forced them to be on site and we troubleshoot the issues with them rather than over the phone. This method allowed us to migrate the servers faster and quicker.

dclee · ‎01-10-2012

Well the good news is that we are a small group here so the Aix and Vmware guys would be in when we did the cutover..

Like I said earlier I dont think I could move it all in one weekend...I am a one man crew here and if I get someone to help me then I'll spend more time fixing what they did than actually doing it myself.

So you see any issues with me trunking the 2 switches together and migrating the servers over a month or so ? In this scenario I would have have servers in the same vlan but spread across both the 6509 and 6513..I am testing this in the lan right now and I dont see a problem with doing it this way. But wanted a few more opinions.

Cheers

dave