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New Member

Router acting as DHCP server, need to add 2nd cable for redundancy.


We have a typical L3/L2 campus network.  We have 2 core L3 switches and 8 L2 switches that trunk to both cores.  Off one core we have a router which is our DHCP server for all our VLANs.  It's IP is and it's gateway is which is the VLAN 21 (HSRP) on the 2 cores.

I want to add a second cable to the DHCP router and add it to the other core for redundancy, I can't put it in the same subnet, is it best I just put it in another vlan the L2 switch can get to?

I think at some point we can get a server where we can give both nics the same virtual IP and bundle them.


VIP Super Bronze

Hi,If the router supports


If the router supports Portchannel, you can put both connections in one Portchannel and use the same IP ( for both links.


New Member

All these years I didn't know

All these years I didn't know a router could do that, I have don't many a tim eon switches.  I've configured it like this, but can't ping from the cores yet.


interface Port-channel1
 ip address
 hold-queue 150 in
interface FastEthernet0/0
 no ip address
 duplex auto
 speed auto
 channel-group 1
interface FastEthernet0/1
 no ip address
 duplex auto
 speed auto
 channel-group 1

ip route is the HSRP address the 2 cores are using.


VIP Super Bronze

Can you post the config from

Can you post the config from the switches?

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