I have 2 physical machines and one failover ip ... I already figured out the network configuration, just added the following to both config files of /etc/network/interfaces
iface eth0:0 inet static
only problem is now that I have problems receiving emails from domains that are configured through ispconfig. Do I have to configure multiple MX-records to each of the physical servers or do I configure only one MX-record to the reverse-dns of the failover-ip? I'd be very thankful to get an answer to that question.