sorry but i didnt get it, u said one key can be sent at a time while i can receive multi keys at the same time ??? how can i receive when multi keys while a router can send 1 at a time ??? in my case key 1 was sent first right which was not valid for RtrB, so wat will happen next ?? key 2 will be sent right ??? i m confused plz explain it

thanks in advance

This link you posted, explains it in details

"Router A will accept and attempt to verify the MD5 digest of any EIGRP packet with a key equal to 1. It will also accept a packet with a key equal to 2. All other MD5 packets will be dropped. Router A will send all EIGRP packets with key 2.

Router B will accept key 1 or key 2, and will use key 1 to send MD5 authentication, since key 1 is the first the first valid key off the key-chain. Key 1 will no longer be valid to be used for sending after December 4, 2006. After this date, key 2 would be used to send MD5 authentication., since it is valid until January 4, 2007. "

You have to make key 1 on Router B invalid in order for Router A to receive key 2 from the chain. You can change this behavior by inserting a time in the past as the start and end time for key 1.

hi sorry edison i m not getting it, see this is how i have configured now,

RtrA

key chain ciscoa

key 1

key-string keya1

key 2

key-string cisco

RTrB

key chain ciscob

key 1

key-string keyb1

key 2

key-string cisco

even now they r not authenticating but why ??? when key 1 is invalid why r they not agreeing upon key 2 ??? u said

"Router A will accept and attempt to verify the MD5 digest of any EIGRP packet with a key equal to 1. It will also accept a packet with a key equal to 2" so why dosent it accepting key 2 in my case ??? i know i m being stupid but i m really not getting it plz explain it

here is a config example

http://www.cisco.com/en/US/customer/tech/tk365/technologies_configuration_example09186a00807f5a63.shtml

suggestion:

turn on debug - "debug eigrp packets" you will see the behavior.

good luck