Preface
Many a times, simple things can bite you when you are planning something really important, like a jumping the gun for virtual IP installing 10gR2 CRS.
The CRS installation assumes that the virtual IP hostname and IP information should be either in the DNS or in local /etc/hosts file ONLY. It does not assume that the virtual IP is already tied up to a network interface on the RAC nodes.
A cryptic error...
If the virtual IP is already attached to network interface during the CRS install, it throws a cryptc error, saying " the virtual interface seems to be already assigned to another system in the network ", which can be pretty misleading. We faced this situation recently during one of our upgrades:
, The problem...
The problem was that the racprod1-vip virtual hostname was already associated with a network interface alias lan1:801:
Please note: The hostnames, domain and IPs mentioned in this diagram are completely fictional and have been fudged from their original values. The current representation is enough for the sake of illustration.
