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Finding port and connected server on Switch

Hi Experts ,

4507 R switch ---- FW...

Actually Vlans are defined on Nortel FW and servers are connetcted on 4507 R switch.

I know that show mac-address-table | in mac address will show the port details on which server is connected..

But in this scenario we have mac addresses of servers but we are not getting the exact port on which respective server is connected..coz vlan's are defined on Nortel FW.

Is there any command to know the port on which server is connected....using mac address of server.I mean i want to know which server is connected on which port of 4507 Switch.

So many servers are connetcted on 4705R and checking physically one by one is very difficult...

Thanks in advance.

Cheers :)



Re: Finding port and connected server on Switch

even if you have a Nortel FW, you should be still enable to find your servers, if they are really connected to your 4507 switch!. teh switch dynamically learns MAC @.

i can't understand what do you mean by vlans are defined in Nortel fw.

what are you getting when using:show mac-address-table | in mac address ?

New Member

Re: Finding port and connected server on Switch


Try this, show mac address-table address "mac-address of server"


Re: Finding port and connected server on Switch

Hi ,

Vlan's are defined on Nortel FW and we are allwoing that vlan through trunk port of Switch...and servers are placed in respective vlan's on 4507 R switch.

Ex : 4507 R switch Gig 2/1---Trunk port (allow only vlan 52)---G0/0 of Nortel FW.

FW config :

Vlan 52

ip address

4507R switch :

Int g2/2

switchport mode access

switchport access vlan 52

description : IVR server

In this case we know that IVR server is connected on gig 2/2.

But so many servers are placed in Vlan 52 on 4507R without description.I want to know on which port which server is connected...

I have mac-addresses of servers which falls under vlan 52 which is taken from Nortel Firewall.But if i want to findout the port using command show mac-address-table | in mac-address I am not getting the port details of the server.I mean exact port and respective server connectecd in that port.

Cheers :) MSK

Hall of Fame Super Blue

Re: Finding port and connected server on Switch


Not sure what you are asking here.

The switch will record which mac-address is on which port. If there is no description on the port then there is no technical way to get it ie. it needs to have been entered by the net admin.

The Fw will have all the IP to mac-address mappings. So if you have an IP address of a server then find it's mac on the firewall and then run "sh mac-address etc..." on the switch and you will find out which port that server is attached to.

If you have the mac just go straight to the switch.



Re: Finding port and connected server on Switch

Hi Jon ,

Thanks for reply...As you said i need to find out which port that server is attached to on 4507R switch.

I did following things..

1.I got mac-addresses of servers from Nortel Firewall.

2.executed the command "show mac-address-table | in server mac address on 4507 R switch..

i am getting nothing after executing above command..actually we should get output like

4507 R#sh arp | in

Internet 203 0080.4215.4879 ARPA Vlan103

4507 R#

4507 R#sh mac-address-table | in 0080.4215.4879

103 0080.4215.4879 dynamic ip GigabitEthernet3/16

But I am not getting port details after executing show mac-address-table command for vlan 52 series servers.

Note : Vlan 52 is defined on Nortel Firewall and trunk link configured between 4507 R and nortel Firewall which allows vlan 52.



New Member

Re: Finding port and connected server on Switch

Agree with the last post.

show mac-address-table vlan 52 or even | include Vlan 52 (double check how it shows perfectly in the original command and match it).

Should give you a list of macs in VLAN 52. If you see the mac on a trunk port you can conclude it is in another upstream switch.

If you are not getting an output on your switch after you enter the filtered command than I am sorry to say that that mac-address is NOT on that switch. Which means your server is most likely to be plugged in somewhere else.


New Member

Re: Finding port and connected server on Switch

The IOS command is:

sh mac add vlan 52

This will list all MAC addrs the switch knows for vlan 52 and show the ports for those MAC addrs.

If there's a port shown for a MAC addr that is not on the 4507, then it's a MAC addr learned from another switch that is trunked together and has a vlan 52 defined.

Then you can check the MAC addrs from the switch with those on the firewall to get an IP addr, then you can check the IP addr against a DNS zone or a hosts file to get a name (assuming the DNS or hosts file has the info).