Daily Archives: February 24, 2013

3.7.b Implement and troubleshoot IBGP and EBGP

3.7.b [i] EBGP, IBGP

i will paraphrase for a change…

1) a tcp connection request must have a matching source address in a bgp neighbor statement

R2#sh tcp brie
TCB       Local Address               Foreign Address             (state)
67F71058  2.2.2.2.179                 1.1.1.1.19300                ESTAB
67F709D4  2.2.2.2.179                 3.3.3.3.25648                ESTAB

R2#sh run | b bgp 123
router bgp 123
 bgp log-neighbor-changes
 neighbor 1.1.1.1 remote-as 123
 neighbor 1.1.1.1 update-source Loopback1
 neighbor 3.3.3.3 remote-as 123
 neighbor 3.3.3.3 update-source Loopback1

2) the router bgp asn statement must match the neighbor router’s reference to that asn in its remote-as statement

R4#sh run | b router bgp
router bgp 45
 bgp log-neighbor-changes
 neighbor 3.3.3.3 remote-as 123
 neighbor 3.3.3.3 ebgp-multihop 2
 neighbor 3.3.3.3 update-source Loopback1

R3#sh run | b bgp 123
router bgp 123
 bgp log-neighbor-changes
 neighbor 1.1.1.1 remote-as 123
 neighbor 1.1.1.1 password cisco
 neighbor 1.1.1.1 update-source Loopback1
 neighbor 2.2.2.2 remote-as 123
 neighbor 2.2.2.2 update-source Loopback1
 neighbor 4.4.4.4 remote-as 45
 neighbor 4.4.4.4 ebgp-multihop 2
 neighbor 4.4.4.4 update-source Loopback1

3) the bgp rid’s have to be unique…

R4#sh ip bgp neigh
BGP neighbor is 3.3.3.3,  remote AS 123, external link
  BGP version 4, remote router ID 3.3.3.3

R3#sh ip bgp neigh 4.4.4.4
BGP neighbor is 4.4.4.4,  remote AS 45, external link
  BGP version 4, remote router ID 4.4.4.4

4) if used, md5 authentication must be successful

*Feb 24 16:16:46.532: %TCP-6-BADAUTH: Invalid MD5 digest from 3.3.3.3(39907) to 1.1.1.1(179) tableid – 0
R1(config-router)#neigh 3.3.3.3 pass cisco
R1(config-router)#
*Feb 24 16:16:53.648: %BGP-5-NBR_RESET: Neighbor 3.3.3.3 reset (Peer closed the session)
*Feb 24 16:16:53.660: %BGP-5-ADJCHANGE: neighbor 3.3.3.3 Down Peer closed the session
*Feb 24 16:16:53.660: %BGP_SESSION-5-ADJCHANGE: neighbor 3.3.3.3 IPv4 Unicast topology base removed from session  Peer closed the session
R1(config-router)#
*Feb 24 16:17:06.304: %BGP-5-ADJCHANGE: neighbor 3.3.3.3 Up
R1(config-router)#

brick by brick, my citizens…

coffee and me and ccie…

gotta have it… i oughta invest in a coffee bean processing plant… i’ve found ccie goes down better with coffee and cream… actually, it’s the jolt that i’m in it for…

when i finally made ccnp and went back to the front desk at the testing center the girl there asked my why i wasn’t smiling… she told me to celebrate… i lied and told her i was sad that i wouldn’t be seeing her again for a year at least… i took my paper, went out to my car and cried…

it was a release, but it was also a fear of the future… a chapter closed but the abyss just opened up… the pain and struggle just renewed with a different set of rules…

legend has it that scott morris was asked how he felt after passing his first ccie… he responded something to the effect that he now realized how little he knew…

 

ccie quick ref…

to use it as a study aid is good…  but i have another idea… like ruhann who went and made his own study materials for ccie… that is a good idea… when you take the time to write something down, reread it, tinker with it, edit it, you will come to know it better in the end…

this is work; there is no time for slacking… slacking is for the guy who dreams of passing the ccie lab but who puts no real effort behind it… no short cuts…

like ccnp route, i began a spreadsheet to chart my time for ccie… why? so i can look at it later and say, wow, look at the time i’ve put in, i’m so wonderful? hell no… so i can look at it while i’m making the entries to realize where i need to spend more time, where i’m coming up short…