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New Member

Passive & Non passive!

Hello Netpro!

IF we have a Dist switch connected to CORE Thr Portchannel;AND THIS Dst has 10 L3 Interfaces;EIGRP IS THE Routing protocol

Why its recomended to configure all L3 interfaces as Passive interface & the Portchannel as non passive interface.is any matter regrding performance or EIGRP Best practice?WHY IN THIS ISSUES WE CONFIGURE THE PASSSIVE INTERFACE?

regards

ALI

1 ACCEPTED SOLUTION

Accepted Solutions

Re: Passive & Non passive!

Ali,

If a layer 3 interface isn't passive EIGRP will send multicast (224.0.0.10) hello packets on that segment looking for neighbors. If there's another device on the same segment that runs EIGRP they will become neighbors and will exchange routes between them.

HTH

Sundar

4 REPLIES
Hall of Fame Super Blue

Re: Passive & Non passive!

Hi Ali

If the port channel is layer 2 then you cannot make all your l3 interfaces passive otherwise there won't be an EIGRP neighbourship between the core and distribution switches.

if the port channel is layer then yes you can make your EIGRP L3 interface passive. This aids in troubleshooting and unnecessary EIGRP updates across the links.

HTH

Jon

Hall of Fame Super Blue

Re: Passive & Non passive!

Sorry Ali, that should say

"if the port channel is layer 3 then yes you can make your EIGRP L3 interfaces passive".

Jon

New Member

Re: Passive & Non passive!

Hi Jon!

ofcourse L3 Portchannel;what if we didn't configure passive interface;how EIGRP routes will propogate?

10xs

Re: Passive & Non passive!

Ali,

If a layer 3 interface isn't passive EIGRP will send multicast (224.0.0.10) hello packets on that segment looking for neighbors. If there's another device on the same segment that runs EIGRP they will become neighbors and will exchange routes between them.

HTH

Sundar

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