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Mike Satterfield
 asked on

Can't Assign Static IP on Cisco switch, but DHCP works

I have several stacks of cisco 3750x switches at the school I am working at. Each stack is configured the same, just on different Vlan's.

On one of the stacks I can't assign a static IP address to anything, even though DHCP is working fine. I can pull a DHCP address. and it works, but if I statically assign that address to a laptop it won't work, I have tried multiple ports/ multiple vlans.

this is not a subnet or gateway mistake on my end.

I am attaching the running config for the stack.  

I have tried multiple ports but the most recent was gi4/0/33 It's currently  set to vlan 32, however I had the same problem while it was set to vlan 24.

Thanks for your expertise.
Switches / HubsNetwork Management

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Last Comment
Craig Beck

8/22/2022 - Mon
NetExpert Network Solutions Pte Ltd

While you assign the static ip address to the workstation, will you able to ping to your gateway ip address?

do you able to see the workstation mac address on the core switch?

Did you hard-coded anything like auto-discover mac address on the core switch ?
Mike Satterfield

I was not able to ping the gateway address. I did not do a search for the mac address..  nothing like that is hardcoded.  
NetExpert Network Solutions Pte Ltd

Lets troubleshoot the issue for one PC

connect your laptop to the stack switch
assign static ip address to the laptop
check the laptop mac address in both stack switch as well as on the core switch.

if you can't see the mac address on the switch,  remove the port-security command on the switch port and try again
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Walt Forbes
Mike Satterfield

not only can't i see the mac address.. port shows not connect. (i never disconnected it) and while the local lan is showing a configured IP the same as the dhcp, when i do an ip config it gives me a 169.x.x.x. address.

I change the nic back to dhcp .. it re-identifys grabs an address and the port shows connected.

it has to be some kind of security setting right ??

current  port configuration

interface GigabitEthernet3/0/33
 description Client Access Port
 switchport access vlan 32
 switchport mode access
 switchport nonegotiate
 switchport voice vlan 25
 ip arp inspection trust
 srr-queue bandwidth share 10 10 60 20
 queue-set 2
 priority-queue out
 mls qos trust device cisco-phone
 mls qos trust cos
 macro description CLIENTPORT | CLIENTPORT
 auto qos voip cisco-phone
 storm-control broadcast level bps 50m 25m
 storm-control multicast level bps 50m 25m
 storm-control action shutdown
 service-policy input AutoQoS-Police-CiscoPhone
NetExpert Network Solutions Pte Ltd

It's pretty much clear that the port security blocking you if you  static ip on the laptop.

If you would like to confirm ,  remove the macro configuration under the interface and try
Craig Beck

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Mike Satterfield

I have removed the macro and no-change.

I will run the no ip arp inspection vlan 32 on the port first thing tomorrow.

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Craig Beck

Run it in global config, not on the port.