Using Nmap to Fix a Problem
Mar 05, 2010, 22:02 (0 Talkback[s])
[ Thanks to Jay Fink
for this link. ]
"Fixing a Problem with Nmap
"Ever had an ipv4 network address that is supposed to migrate
over via a high availability mechanism simply not work or even
stranger if there were several addresses some do and some do not?
An experienced network administrator probably has seen mysterious
non-migrating addresses, however, within this context is presented
a rather interesting solution to when it has been observed.
"For simplicity two addresses will be used, the idea being if a
service or server in part of a 2 node high availability cluster are
detected down via a heartbeat check the node that is up takes over
(unless it is the one already holding the addresses). There are
some details that need to be presented as well:
"The compute nodes are on the same logical but different
physical networks and communicate via a switch.
"There is a cisco global site selector in front of the compute
"The compute nodes are running a recent version of Red Hat