Win2003 - NAT outbound mappings deleted for TCP connections

[Vibhor Mahajan]

Hello,

I have configured NAT on Win2003 server (SP2). Local address for NAT
is
192.168.25.x and global interface IP address is 10.0.1.179.

Client application: runs on computer inside NAT
Server application: runs on computer outside NAT

Server listens for TCP connections on port no. 1334. Client connects
twice
to server using TCP.

But after a random amount of time, first TCP connection mapping is
deleted
on NAT server. netstat -n command used on both client and server
after
mapping is deleted shows connection in ESTABLISHED state. When server
or
client closes connection then fresh mapping is again created at NAT
server.

Since mapping is deleted, server and client are not able to send \
recv data
using this TCP connection. Data transfer on 2nd connection is OK.

Moreover, mapping is only deleted when client is behind NAT server and
our
server is not behind NAT. If server is behind NAT and client is
outside then
this problem is not coming.

Kindly suggest why NAT server is deleting the mapping and how can it
be
stopped?

PS: If this is not the right newsgroup for above question, kindly
suggest
suitable newsgroup.

Thanks in advance.

Best Regards,
Vibhor

[David Schwartz]

On Aug 14, 12:39 am, Vibhor Mahajan <mahajan.vib...@gmail.com> wrote:

> But after a random amount of time, first TCP connection mapping is
> deleted
> on NAT server. netstat -n command used on both client and server
> after
> mapping is deleted shows connection in ESTABLISHED state. When server
> or
> client closes connection then fresh mapping is again created at NAT
> server.

Are we talking seconds? Hours? Days?

DS

[David Gravereaux]

I'm thinking the DHCP lease is expiring and the host isn't re-establishing.

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