Some switches client not able to get automatic IP address From DHCP configured at CORE Switch

[fransglobel]

Dear All,

Hope you are doing well!

Please help us to solve the issue

Am facing a trouble to troubleshoot my LAN Network

Our Network is like we have CORE switch as server and reset switch as client and on that we have configured 45 Vlan's according to their departments and different DHCP as per VLAN.

We created VLAN No 46 for VOICE phones, everything work's good all the switches had the information of VLAN 46 some switches near to CORE are getting IP Address from VLAN NO 46 DHCP and phones are getting registered but the problem is almost 75 percent is not even able to get ip address from VLAN 46

we tried to make another vlan but same issue

Please help me or give some guidance to troubleshoot.

Thank's & regards

Nitin

[Jitender Bhandari]

Hi Nitin,

make sure the IP helper address is configured correctly if you have the devices and DHCP on different VLAN, see below.

https://www.freeccnaworkbook.com/workbooks/ccna/configuring-an-ip-dhcp-helper-address

JB

[paul driver]

Hello

So to confirm your phones are not obtaining DHCP, if that is the case, have you changing the voice port into an access port and attach a pc and see if you obtained addressing then?

Do the phones require CDP, if so is that enabled, and are your trunks allowing both the voice and access vlans.

Have you applied any debugging, if not try enabling:

deb ip dhcp server packet
debug ip udp

@Nitin,

My understanding is in this scenario dhcp relay would not be required as Lan core switch is running as the dhcp server.

res
Paul