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Re: multi-homing fixes

  • From: Larry Sheldon
  • Date: Sat Aug 25 13:04:46 2001

> > Do you *really* want your DNS TTL set down in the same range as
> > the time for a BGP route fall-over?
> Ever read RFC1123?
> It states:
>  2.3  Applications on Multihomed hosts
>       When the remote host is multihomed, the name-to-address
>       translation will return a list of alternative IP addresses.  As
>       specified in Section, this list should be in order of
>       decreasing preference.  Application protocol implementations
>       SHOULD be prepared to try multiple addresses from the list until
>       success is obtained.  More specific requirements for SMTP are
>       given in Section 5.3.4.
>       When the local host is multihomed, a UDP-based request/response
>       application SHOULD send the response with an IP source address
>       that is the same as the specific destination address of the UDP
>       request datagram.  The "specific destination address" is defined
>       in the "IP Addressing" section of the companion RFC [INTRO:1].
>       Similarly, a server application that opens multiple TCP
>       connections to the same client SHOULD use the same local IP
>       address for all.
> Unfortunately, many programs have chosen not to do this.

Well, yes.

But I thought the thread was talking about multi-homed _networks_,
which I take to be a different problem from multi-homed _hosts_.

Am I in over my head again?