Etherchannels and Passive Interfaces in EIGRP configurations

[Kwaku Paintsil]

Hi, I was just wondering, if I am configuring EIGRP on Layer 3 switches and I want to make passive interfaces for my exit interfaces to my Private Network(Layer 2 Switches). Am I able to add interfaces which I have configured as Etherchannels to the passive interfaces?

[Georg Pauwen]

Hello,

do you have a layer 3 port channel to your home network ? Hello packets are sent on layer 3 interfaces only as far as I recall. If the port channel is L3, you can make it passive.

[Kwaku Paintsil]

Thank you @Georg Pauwen  for your response 

[Giuseppe Larosa]

Hello @Kwaku Paintsil ,

only the port-channel interface if configured for L3 operation

like

int port-channel 1

no switchport

ip address 10.10.10.1 255.255.255.0

in this case the port-channel 1 can be made passive under the router eigrp configuration you don't need to configure passive for the member links. From the point of view of EIGRP  / IP routing the port-channel is  a single logical link.

if your port channel is configured as a L2 802.1Q trunk carrying several VLANs it is like it does not exist for EIGRP and you should passive the SVI interfaces of user facing VLANs.

Hope to help

Giuseppe

[Kwaku Paintsil]

Thank you @Giuseppe Larosa  yes my port channel has been configured as a trunk for carrying vlans. This being the case I will configure the SVI interfaces of the user facing the vlans. 

[Giuseppe Larosa]

Hello @Kwaku Paintsil ,

your understanding is correct being the port-channel a L2 trunk the EIGRP passive interface can be configured for each SVI associated to each VLAN allowed on the trunk where only end user devices are connected.

Hope to help

Giuseppe

[balaji.bandi]

If this is Layer 2 Port-channel you not required to do, you need to only do passive-interface on Layer 3 SVI which is passing inside Port-channel.

[paul driver]

Hello

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@Kwaku Paintsil wrote:

Hi, I was just wondering, if I am configuring EIGRP on Layer 3 switches and I want to make passive interfaces for my exit interfaces to my Private Network(Layer 2 Switches). 

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EIGRP is a Layer 3 routing protocol so it wont run on layer 2 switch interconnected trunks, So if your portchannels connectiing to your lan switches are all layer 2 then eigrp and passive interfaces are not applicable.

[Joseph W. Doherty]

Although already correctly answered by the other posters, just to be clear, you would only have a "passive" EIGRP setting for the interface with an IP.  Shouldn't matter what the underlying "physical" interface(s) is/are.