ipsec and dns

[Antony Gelberg <antony@wayforth.co.uk>]

Hi all,

I use openswan as a road-warrior.  No issues with the connection, all is
good.  However, when the VPN is up, I'd like to use a different DNS
server (one across the VPN) than the one that the local DHCP server
provides.  I have:

supersede domain-name-servers 192.168.168.10

in dhclient.conf, but this breaks when I'm out and about with no VPN
(such as roaming with a 3G card - but why that doesn't work is a
different matter).

Anyone know of anything that I can investigate to make this work more
seamlessly?  In summary, when the VPN is up, I want DHCP to use the
above server.  Down, I want it to use whatever DHCP suggests.

Antony