Wifi Router Can't be seen on switch port after topology/vlan change

[Jonnyballgame34]

Greetings---Have unique situations, and not sure which information to post as a starting point, so if you have questions/ideas, please let me know and I'll get whatever information you need.  Thanks in advance for the help.  

I inherited a big, poorly planned site move.  this included changes to the topology and now I have a problem that didn't exist at the old site. 

Old Site:   Engineers had a 2960 switches at their desks that connected directly to the core.  Relevant vlans were

701--testing Vlan ports fa0/1-6  (dhcp)

106 User Vlan  (dhcp)

1   Management Vlan

The engineers would also plug a wireless router into port 1, (vlan 701), to test other devices.  The router would pick up a DHCP address on Vlan 701, and they'd configure it/change/ etc. from the PC. This worked fine. 

The following significant changes were made

-Management Vlan was moved to Vlan 20.   

-Instead of connecting directly to the core, the 2960's connect to access switches, (also 2960's), that connect to the core.

Since the move was completed, the Wifi router will no longer pick up a DHCP address when connected to the 2960, and its MAC address doesn't even appear in the table.   It does show as connected and up/up. 

Other devices will pick up address without problem if plugged into one of the ports assigned to that Vlan.  The Wifi router won't pick up an address in any port. 

Not really sure where to start with this.  I removed portfast and bpdu guard---tried moving around vlans, but I I still can't get it to see the MAC of the connected Wifi.  

I should also mention that I just added PIM routing to the core to solve another problem.  No one onsite to test, but not sure if the problem with UDP packets getting knocked down would be related. 

Any help would be appreciated--again, please let me know what other information would help.  Not sure if this is clear.  Thanks

[Georg Pauwen]

Jon,

since all the other clients on your 2960 switch successfully obtain DHCP leases, I tend to think that the issue is with your wireless router configuration rather than the access port. Do all switches run the same IOS version ? You might want to try out the different options of the 'ip address dhcp' command on the Ethernet interface your wireless router is connected to.

[Jonnyballgame34]

Hi Gpauwen,

Thanks very much for taking the time to look at my question.  I thought similar about the wifi router settings, but ran into to issue with the theory

-multiple people have the same model of switch and wifi router, and none of them work anymore

-they all worked at the previous site

I"m not sure what you mean about changing dhcp options on the port--the core switch is the dhcp switch, the others are just access trunked to the core, and desktop trunked to the access.

As far as the IOS goes, do you mean all of the desktop switches, or do the desktops, access, and core all match?  If it's the latter I will look when the vpn lets me login.  I wouldn't be surprised if they are different because the desktop switches were sitting around for a while, while the access switches and core are new infrastructure.  Do you think that could be the problem?

Arg---this is what happens when you aren't given any opportunity to test and make wholesale changes.  Thanks again

Jon

[Jonnyballgame34]

It looks like they are not the same----you think update is worth trying?  See attached.  Thanks again,

Jon

[Georg Pauwen]

Jon,

the acccess port where the wireless is connected to has the 'ip address dhcp' command configured, I assume. That command has numerous options, my guess was that you could try to configure those and see if it makes a difference.

I will run the IOS version through the Bug tool, and report back...

[pwwiddicombe]

The 2960's are configured with a trunk uplink that used to go the core, presumably correctly configured as a trunk port.  In the new environment, is it a trunk to the access layer switches they connect to, and do the ACCESS LAYER switches have those particular VLANS trunked to the core?

[Jonnyballgame34]

HI,

Thanks to you as well for looking................all trunks---desk switch-access switch-core switch have all vlans allowed on their trunks.  And other devices on the same switch are able to pick up Ip's on that same subnet.  

I"m inclined to agree with gpauwen about the problem being on the wifi routers, but I can't reconcile why they would have worked on that switch at the old location, and not work at the new one, unless it's related to the networking changes. 

[Georg Pauwen]

Jon,

no bugs found in either IOS release. Changing the software to the same as the switch that actually DID work might be worth a try...