Clients unable to receive IP adress

[kustaruni]

Dear Community Members,

i have been experiencing a strange issue from the past couple of days, clients are unale to receive ip address from a specific vlan however on the same switch other dhcp enabled vlan are fine. we have confirmed the reachable from switch to server its fine. IP helper address is defined under interface vlan on distribution switch. when i run packet capture on client machine i can see that clients are broadcasting for IP but not receiving any response please refer to screen shot one more thing static IPs on same vlan are working fine

[Georg Pauwen]

Hello,

what are you using as DHCP server ? Post the full config of your switch...

[kustaruni]

we are using MS windows server 2012

distribution switch config (L3)

interface Vlan42
 ip address 10.11.42.1 255.255.255.0
 ip helper-address 10.10.2.11

[Georg Pauwen]

Post the full configuration of the switch. Are the clients directly connected to THIS switch, or are there access switches connected to the distribution switch ? If there are access switches, post the full configuration of one of those as well...

[rtmtoky]

Hi,

I'm a beginner too and I am not very good in english but I can give you some ideas to troubleshoot your problem. Assign manually an IP address (belong to the network of your gateway) to your host and ping your gateway. If you can't reach your gateway, check if your switch has ip dhcp snooping activated, if it has, turn it off temporarily to test if it can resolve our problem.

Regards Toky,

[kustaruni]

hello nrtmtoky

as i mentioned static IPS are working fine only having issue with DHCP, switches were not configured with snooping after this issue came i enabled snooping to avoid any rouge dhcp sever in the lan

[rtmtoky]

At this point, it is a good idea to post the file config of your switch as Georg Pauwen asked ;)

[andrew.butterworth]

What type of DHCP server is it?  Have you checked that the scope just isn't exhausted and the server just doesn't have any free addresses?

[Richard Burts]

Am I correct in understanding that there are other vlans on this switch that are successfully receiving IP address assignment using DHCP to this same server? And am I correct in understanding that this vlan was working and then stopped working?

Have there been any config changes on the switch? Have there been any config changes on the DHCP server? Can you check the logs on the server and look for any messages about this vlan and its scope?

HTH

Rick