Natting issue using a virtual IP on 2507 router

Natting issue using a virtual IP on 2507 router

Post by manu00 » Mon, 26 Jan 2004 03:11:02

We have a Microsoft cluster server with 2 nodes each having a IP
address mapped to it ( and ) anda
virtual IP address ( . This server is connected a
Cisco 2507 router's ethernet port. WE have a primary and secondary IP
address assigned to the ethernet port as follows :-
and .
This router's serial 0 is connected to external network with IP range
of .
Our ethernet port has a following NAT command

ip nat inside source static
ip nat inside
serial 0
ip nat outside

Problem: we are able to ping the outside world from the router however
ping fails when we ping the outside world from the server.
When we change the NAT statement as follows
ip nat inside source static
we are able to ping the outside world.

1. When we use either of the node IP's to ping it works
2. with natting of virtual IP of the cluster , Ping fails
3. Extended ping from the router fails when source address is taken as
4. With source as the ping is successfull.

Any help on the issues will be highly appreciated, If any other info
is required please let us know.

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