cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
380
Views
0
Helpful
7
Replies

4506 dhcp issue

mohamedelkady
Level 1
Level 1

we had a daily-basis ip conflict with dhcp server on cisco switch 4506E specially after replacing some the users' ports or a user using the laptop and moves alot, the ip conflict is detected using GARP method.

note: the user could try multible free IPs till gets one ip and gets them all excluded from the pool (conflicted )except the last ip he took and there are no additional configuration for dhcp on the switch, just the pool and the manual excluded IPs

we don't use "no ip dhcp conf log" or "ip dhcp conf resolution" as it is just a temp solution for the issue itself.

so what could be causing the issue and how to resolve it permanently?

7 Replies 7

Leo Laohoo
Hall of Fame
Hall of Fame

@mohamedelkady wrote:
the user could try multible free IPs till gets one ip

Please explain the meaning of this?

using "sh arp" with the mac that making that conflict issue

you can see that mac associated with different IPs and only one of them are the pingable one and the one the user get assigned

and the other IPs in the "sh arp" were transfered to the conflict and Block List.

using "sh arp" with the mac that making that conflict issue

you can see that mac associated with different IPs and only one of them are the pingable one and the one the user get assigned

and the other IPs in the "sh arp" were transfered to the conflict and Block List.

SW#sh arp | i 6c02.e097.ad36
Internet 192.168.6.160 40 6c02.e097.ad36 ARPA Vlan6
Internet 192.168.6.184 5 6c02.e097.ad36 ARPA Vlan6

Can I see config of port you use for endpoint

MHM

interface GigabitEthernet1/2/8
switchport access vlan 6
switchport mode access
switchport voice vlan 10
spanning-tree portfast

Show ip traffic statistics <- share this 

MHM

Review Cisco Networking for a $25 gift card