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 6.1.3.4, 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?
On Sat, Aug 25, 2001 at 12:02:33PM -0500, Larry Sheldon wrote:
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
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?
If we define a network as something, which consists of: clients and servers (hosts) - then the problem on hosts could be solved with DNS as above. Clients could be either: 1. NATed behind a HSRPish device so that they always use the same IP, and the NAT device translates to whichever uplink is currently active or 2. Reconfigured if one link should be down -- Med venlig hilsen / Sincerely Andreas Plesner Jacobsen (Network Engineer) / Tiscali A/S (World Online) Peter Bangs Vej 26, DK-2000 Frederiksberg - http://www.tiscali.dk Tlf. +45 3814 7000 - Fax +45 3814 7007
participants (2)
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Andreas Plesner Jacobsen - Tiscali
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Larry Sheldon