Re: [OSL | CCIE_RS] BGP design question

Marko,

When you tested this feature, did you test the latency, like when the
primary comes up after a failover and the back up letting go of the routes?
OR when the B/up actually takes over?

I tested this feature when it first came out in 12.3 T something code (I
don't remember) and i had to play around with timers to speed up
convergence, and even then, it was kind of slow to converge between PRI to
B/up and or from B/up to Prim failover, and *having the routers inject the
routes with the correct next-hop. *
I will try to find that lab (Don't hold your breath, it was a long time
ago), But when i tested it, the second BGP detected an adjacency change, it
terminated the session, but this termination was NOT immediate (Once again,
PRI---B/up and/or B/up to PRIM and advertising the correct next-hop to the
other routers), this was between Scan intervals, and when i tried it few
times to see the range, i noticed that once awhile it took 15 seconds to 30
seconds.

May be it was a flaky IOS, but if you have tested all this and it actually
works like advertised, then, it is a nice solution. But you see with static
routes and EEM i don't need to worry about any of the issues.

On Sun, Mar 28, 2010 at 10:05 AM, Marko Milivojevic <markom_at_ipexpert.com>wrote:

> On Sun, Mar 28, 2010 at 17:00, Narbik Kocharians <narbikk_at_gmail.com>
> wrote:
> > Totally understand that, but i did not see any mention of OSPF or ISIS.
>
> Enjoy.
>
> R1:
>
> interface Loopback0
> ip address 1.1.1.1 255.255.255.255
> !
> interface FastEthernet0/0
> ip address 12.12.12.1 255.255.255.0
> !
> ip sla 1
> icmp-echo 12.12.12.2
> frequency 5
> !
> ip sla schedule 1 start-time now life forever
> !
> track 1 ip sla 1 reachability
> default-state down
> !
> ip route 2.2.2.2 255.255.255.255 12.12.12.2 track 1
> !
> route-map Neighbor-Alive
> match source-protocol static
> !
> router bgp 1
> neighbor 2.2.2.2 remote-as 2
> neighbor 2.2.2.2 update-source Loopback0
> neighbor 2.2.2.2 ebgp-multihop 2
> neighbor 2.2.2.2 fall-over route-map Neighbor-Alive
> !
>
> R2:
>
> interface GigabitEthernet0/0
> ip address 12.12.12.2 255.255.255.0
> !
> router bgp 2
> neighbor 1.1.1.1 remote-as 1
> neighbor 1.1.1.1 ebgp-multihop 2
> neighbor 1.1.1.1 update-source Loopback0
> !
>
> Notice what happens on R1 as soon as I shut down the port on R2 (there
> is a switch between them).
>
> *Mar 29 00:59:19.679: %TRACKING-5-STATE: 1 ip sla 1 reachability Up->Down
> *Mar 29 00:59:19.683: %BGP-5-ADJCHANGE: neighbor 2.2.2.2 Down Route to peer
> lost
>
>
> --
> Marko Milivojevic - CCIE #18427
> Senior Technical Instructor - IPexpert
>
> YES! We include 400 hours of REAL rack
> time with our Blended Learning Solution!
>
> Mailto: markom_at_ipexpert.com
> Telephone: +1.810.326.1444
> Fax: +1.810.454.0130
> Web: http://www.ipexpert.com/
>

-- 
Narbik Kocharians
CCSI#30832, CCIE# 12410 (R&S, SP, Security)
www.MicronicsTraining.com
Sr. Technical Instructor
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