BGP problem to expire holdtimer

Maria Jan Matějka jan.matejka at
Thu May 17 13:33:53 CEST 2018

On May 17, 2018 12:56:22 PM GMT+02:00, Mattia Milani <mattia.milani at> wrote:
>Hello all, i'm writing hear because i have a problem with some
>that i'm making, the simulation is on my laptop with VM.
>I'm focusing on the hold timer expiration, i want to make this timer
>and see the differences.
>This is my topology:
>H1 and H5 are the only one that share some route, i'll call them R1 and
>So when the network it will be stabilized, in all RT (H1,H2,H3,H4,H5) I
>will have 2 voice, one to reach R1 and one to reach R2.
>In every host i setted an hold timer = 3 for every session, with this
>hold time 3;
>Now i want to "kill" the node H3 and see this result: after 3 seconds
>in the RT of H2 and H4 a variation, like one cannot more reach R1 and
>other one cannot reach R2.
>How can i do it? i need to disable something?
>because i tried this:
>1)using the command: birdc -s socket_H3 down and shutting down the VM
>i see that the process that is shutted down, but the other simulation
>changed immediatly the RT
>so i tried:
>2)use only the command birdc -s socket_H3 down and get active the VM
>i was thing that there was a checking on the interface if it is active
>But it didn't work, the RT of others changed istantly.
>3) so i was thinking that before closing itself bird send a signal to
>bird connected (i didn't search in the code) so i use the command "sudo
>kill -9 *pid*" on the pid of the bird relative to H3, but with a big
>surprised i see that not only the process associated with H3 is killed
>it will be closed the process of H2 H3 and H4
>i'll try to explain it better:
>Process list:
>100   Bird_H1
>101   Bird_H2
>102   Bird_H3
>103   Bird_H4
>104   Bird_H5
>i use "sudo kill -9 102"
>process list resulting:
>100   Bird_H1
>104   Bird_H5
>The survives is only the process that was sharing some route.
>do you have any suggestion to see the expiration of hold timer in act?
>Thanks a lot,

Sent from my Android device with K-9 Mail. Please excuse my brevity.

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