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Devices behind Extension Catalyst switch not receiving dhcp

9ja
Level 1
Level 1

I have a problem I urgently need help with. A new room needed an extension switch so I added one. This is the connection I have in my environment:

6509 = running EIGRP. This is the distribution/core switch (collapsed core if you will). The DC/DHCP server hangs off this switch.

3650G = IDF switch but is running as a layer 3 switch hence an EIGRP neighbor to the 6509. IP-helper is configured here and all devices connected to access ports get DHCP no problem.

 

3560G-(ext) = this is the extension switch off the 3560G-IDF switch. All devices here are not getting DHCP. 

 

I have had the 3560G-ext both as a layer 2 only switch with trunk port to the 3560G-IDF switch and also as a layer 3 switch becoming an EIGRP neighbor to the 3560G-IDF, still i don't get DHCP messages across regardless of the design. I have also added IP helper to the 3560G-ext switch but the issue persist. Can someone please point me in the right direction to get this issue resolved? 

 

3 Replies 3

9ja
Level 1
Level 1

By the way, if I give any device a static IP, it works fine. 

Hi

Where the gateway for these vlan is configured? on the 3560-IDF or 6509?




>> Marcar como útil o contestado, si la respuesta resolvió la duda, esto ayuda a futuras consultas de otros miembros de la comunidad. <<

the gateway for each VLAN is located on the 3560G-IDF and those VLAN interfaces have the IP helper address configured on them. All devices directed connected to the IDF gets an IP from the DHCP server but those connected to the 3560G-ext do not receive anything.
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