Aggregation and DHCP IP-Helper

[aoun.ameur1]

Hi All,

I have a problem to assign dynamic IP from a Microsoft DHCP to VLANs.

I have installed a cisco 3650 with interVlan configuration.

I have configured the dhcp ip helper under every SVI and also th ip routing between VLANs.

I have configured an aggregation LACP between the cisco 3650 L3 and a cisco 2960.

I have configured an ethernet port in the cisco 2960 to belong to VLAN 101

I have connected my pc to this port and make the assign of ip address as dynamic but i can't have IP (only the 169.254.x.x).

I need to confirm if the problem is linked to the LACP configured between the L3 and the L2 switch or what ?

Best regards,

[pwwiddicombe · Accepted solution]

Give us the results of the following:

1. Traceroute from the switch to the MS DHCP server

2. Configure a static IP address on the workstation with the same parameters as configured on the DHCP scope, and do the same Tracert <DHCP server>. 

These 2 steps will determine if it is a routing/LACP issue, or a DHCP issue.

[Richard Burts]

I agree that the traceroute outputs will help to determine whether the problem is routing/LACP or DHCP. There are some things about the environment that we do not know which would be helpful, including where is the DHCP server and how do you get to it from the client vlans? I think there are some questions about the config that might shed light on the problem. If the PC is connected in vlan 101 then does the interface vlan 101 have an appropriate IP address? Does interface vlan 101 have the correct ip helper-address pointed to the DHCP server? Does the DHCP server have a scope configured for the subnet on vlan 101?

HTH

Rick

[aoun.ameur1]

Sorry for all,

the problem was resolved. I have missed to enable dhcp service which is disable by default in the cisco 3650

Now, delivering dhcp address is on site 

Thanks for all

Keep going and no stop

[Richard Burts]

Thanks for the update letting us know that the problem is resolved. This can serve as a reminder to readers in the forum that sometimes we do need to remember to check and be sure that needed services are enabled.

HTH

Rick