10-22-2013 10:46 PM - edited 03-07-2019 04:10 PM
Hi,
I have a switch 4500 as a Core and dhcp server. In this I have a dhcp pool for the vlan 111.
I have an other switch, 3560. In this I have one port assigned to the vlan 111. When I connect a computer to this port, the computer get a ip, but I can ping the gateway. I look for the computer's mac address with "sh mac address-table" command and I find the mac with the port, but if I look for the same mac in the "core" with the "sh ip dhcp bind" command, I realize that the mac is diferent:
siwtch access:
access(config-if)#do sh mac add | include Gi0/1
111 2c41.380f.60cf DYNAMIC Gi0/1
switch core:
core0#sh ip dhcp bi
192.168.111.124 012c.4138.0f60.cf Oct 24 2013 12:14 AM Automatic
the problem is only with two computers in all the ports of this switch, but if I connect the same computer in other switch in the same LAN it works without problems.
Do you have any idea??
I think the dhcp pool is properly configured because with others computers in other port with the same vlan works perfect!!!
10-23-2013 01:33 AM
Hi try this command to cleAr DHCP bindings:
Clear ip dhcp bind A.B.C.D
And then check it again with
Show ip dhcp bind
Regards
Sent from Cisco Technical Support iPhone App
10-23-2013 08:25 AM
Hi,
I have already tried with this command, but is the same. The mac address and the ip are the same.
Thanks
Sent from Cisco Technical Support iPhone App
10-23-2013 08:33 AM
What is the exact interface configuration?
10-23-2013 08:39 AM
Switchport mode access
Switchport access vlan 111
Switchport voice vlan 140
Before this conf, I had a portsecurity with max 2 and I realized that the port was in err-disable.
But now that the port only has the vlan voice and the vlan access configuration, the port isnt in err-disable but it doesnt work.
Thanks
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10-23-2013 09:20 AM
Hi Carlos,
are you, by any chance, running any multicast?
Because this seems like multicast mac-address (If im correct, it starts with 01) doubt it is a valid host's mac address.
core0#sh ip dhcp bi
192.168.111.124 012c.4138.0f60.cf
Best regards,
Jan
10-23-2013 09:46 AM
Hi,
Yes I have a IPICS connected to the 4500.
But this mac address is a computer. Is it normal that appears lile this?
And why it cant ping to its gateway?
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10-23-2013 10:06 AM
Hi Carlos,
I am sorry, but the MAC addresses are the same and that is not multicast address, my mistake.
The first two numbers are media type (ethernet, in your case)
http://www.freesoft.org/CIE/RFC/1700/24.htm
2c41380f60cf access sw
012c41380f60cf core sw
access(config-if)#do sh mac add | include Gi0/1
111 2c41.380f.60cf DYNAMIC Gi0/1
switch core:
core0#sh ip dhcp bi
192.168.111.124 012c.4138.0f60.cf Oct 24 2
So the problem is somewhere else, the mapping is correct.
Best regards,
Jan
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