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Re: BGP terminology question

  • From: Per Gregers Bilse
  • Date: Tue Nov 08 10:49:42 2005

On Nov  8,  2:39pm [email protected] wrote:
> holdtime-and-a-bit seconds.  [Aside:  shouldn't the session be refused at
> startup if a mutually agreeable keepalive value can't be negotiated rather
> than being allowed to flap like this?]

Junipers seem to be slightly in the wrong here.  A hold time of zero is
acceptable, though unwise, IMHO.  In this case no keepalives are sent,
and the systems have to rely on other means (such as the TCP connection)
to ensure they're both alive, but one could easily imagine a situation
where the TCP connection remains intact after the BGP process has gone
to lunch.  Not good.

In any case, the systems are required to agree on the lowest of the two
proposed hold times, except to note that hold times of 1 or 2 seconds
are not allowed.  Hence, the Junipers should accept and use the proposed
hold time of 0.

  -- Per