How EIGRP offset-list is working here?

[veerendrav2]

Here is my configuration

R6(config-router)#do show ip eigrp topology  
IP-EIGRP Topology Table for AS(1)/ID(6.6.6.6)

Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
       r - reply Status, s - sia Status 

P 5.5.5.5/32, 1 successors, FD is 440320
        via 192.168.1.2 (440320/437760), FastEthernet1/0
P 6.6.6.6/32, 1 successors, FD is 128256
        via Connected, Loopback1
P 10.1.1.8/30, 1 successors, FD is 312320
        via 192.168.1.2 (312320/309760), FastEthernet1/0
P 10.1.1.0/30, 1 successors, FD is 309760
        via 192.168.1.2 (309760/307200), FastEthernet1/0
P 10.1.1.4/30, 1 successors, FD is 2198016   <<<<<============
        via 192.168.1.2 (2198016/2195456), FastEthernet1/0
P 192.168.1.8/30, 1 successors, FD is 284160
        via 192.168.1.2 (284160/281600), FastEthernet1/0
P 192.168.1.0/30, 1 successors, FD is 28160
        via Connected, FastEthernet1/0
P 192.168.1.4/30, 1 successors, FD is 284160
        via 192.168.1.2 (284160/281600), FastEthernet1/0
R6(config-router)#
R6(config-router)#offset-list 1 in 10 f1/0
*Mar  1 01:58:52.471: %DUAL-5-NBRCHANGE: IP-EIGRP(0) 1: Neighbor 192.168.1.2 (FastEthernet1/0) is resync: route configuration changed
R6(config-router)#do show ip eigrp topology
IP-EIGRP Topology Table for AS(1)/ID(6.6.6.6)

Codes: P - Passive, A - Active, U - Update, Q - Query, R - Reply,
       r - reply Status, s - sia Status 

P 5.5.5.5/32, 1 successors, FD is 440320
        via 192.168.1.2 (440320/437760), FastEthernet1/0
P 6.6.6.6/32, 1 successors, FD is 128256
        via Connected, Loopback1
P 10.1.1.8/30, 1 successors, FD is 312320
        via 192.168.1.2 (312330/309760), FastEthernet1/0
P 10.1.1.0/30, 1 successors, FD is 309760
        via 192.168.1.2 (309770/307200), FastEthernet1/0
P 10.1.1.4/30, 1 successors, FD is 2198016   <<<<==================
        via 192.168.1.2 (2198026/2195456), FastEthernet1/0
P 192.168.1.8/30, 1 successors, FD is 284160
        via 192.168.1.2 (284160/281600), FastEthernet1/0
P 192.168.1.0/30, 1 successors, FD is 28160
        via Connected, FastEthernet1/0
P 192.168.1.4/30, 1 successors, FD is 284160
        via 192.168.1.2 (284160/281600), FastEthernet1/0
R6(config-router)#

 Before offset-list update the FD is 2198016 for 10.1.1.4/30 and the below list showing FD & AD (2198016/2195456)

Now take look at after offset-list update. The FD is 2198016, the below list showing FD & AD (2198026/2195456). So my question is why it is showing FD is 2198016, it suppose to show 2198026 like in (2198026/2195456).

And also CCNP Official Cert Guide say the offset-list value is add to computed to FD and AD, but in some blogs the offset-list value is add/computed in delay. which one correct?

[Julio E. Moisa]

Hi

Please let me take a look of your output,The offset-list is an feature used to modify the composite metrics in EIGRP. The value configured in the offset-list command is added to the delay value calculated by the router for the route matched by an access-list. An offset-list is the preferred method to influence a particular path that is advertised and/or chosen.

[Georg Pauwen]

Hello,

issue a 'clear ip eigrp neighbors'. After applying the offset list, the topology database should look like this:

P 10.1.1.4/30, 1 successors, FD is 2198026 <<<<==================
via 192.168.1.2 (2198026/2195456), FastEthernet1/0

[Julio E. Moisa]

Hi,

As George mentioned you can refresh the neighborship, sometime it is not updated immediately.