I'm having some concerns regarding to our core switch replacements.
We have 2 3550s core switch and 6 2960s/2950s and a couple of dozens servers, NAS drives, etc...
The core switches will be replaced with 3750 with ip image license on them.
The trouble is we have more than 20 VLANs with more than 10 HSRP virtual IPs.
I've tried to hook up the new switch with disabled VLAN and HSRP (only layer 2 access) and obviously the servers on the distribution switches strated to loosing the ISP access, because the VLAN and therefore the HSRP vips were disabled on the new switch.
I was thinking to kill the second switch which only has the standby vip HSRP IPs and enable all the VLANs with the HSRP on the new switch.
What would be the safest method to switch over to new HSRP core switch?
(Both 3550 need to be replaced)
The main issue is the live traffic, I can't disable and enable 1 by 1 the HSRPs on the old/new switches because it takes ages.
Our system has dozens of live traffic which can't be interrupted in any way.
I can't put every details onto the picture that I quickly draw, because we have about 100 servers/switches/routers/nas etc...
Also from the picture is missing the routers and the firewall vlans. (all vlans)
Every parts of the network cross connected for redundancy and obviously the picture does not contain that part at all.
I would much appreciate every idea/help how to do it as safe as possible.
Could not find much info regarding to core switch replacement, usually this part of the network has not been bothered much, so therefore less experience/info about this. ;)
There is a picture about the network: http://www.7layer.org/downloads/netw1.png
Thanks very much in advance for every help!