Re: [cobalt-developers] Is it possible to have separate gateways for each NIC on QUBE3?

[zim <zim@xxxxxxxx>]

Ted Behling wrote:

> This is called "multihoming", and will require involvement from your 
> ISPs.  If you don't have a "business-class" DSL account with them, they 
> might not be willing to do this.  See 
> http://linux.oreillynet.com/pub/a/network/2001/05/11/multihoming.html for 
> a neat overview of multihoming.  This is not for the timid.


Another idea to solve this without multihoming
(but with about an hour latency to react to failures):

Run your own nameserver for the domain(s) and give each
server (including the nameserver[s]) a pair of IP-Adresses -
one for the route thru ISP1 and one thru ISP2.

If one connection goes down, you may even automatically
change the nameserver-configurations to reflect the
change in connectivity (although it may take about an hour
[resp. the TTL you gave your address records],
until the cached nameserver data in the net will reflect
the change, hence you risk one hour downtime at most).

The TTL (time to live) should not go below 1 hour
for public data like the IPs of the server.

You may even set up two nameservers - the one reached thru
ISP1 gives only ISP1-addresses back, and the other vice
versa. But in case of a failure after the client got the
address, he will always have to await the TTL of the records
until the cache is refreshed and he gets the right address.
Greetings
Michael
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Michael Zimmermann        hostmaster for Vegaa Internet Services
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