Hey,
I am running Centos 4.4 fully patched and am having a problem PPTP connections.
Right now the PPTP server is on the public network and is working correctly for connections from all clients. We have a private network from behind a firewall, let's call
it firewall A. A single client from behind firewall A can connect with out a problem, however if a second client tries to connect from behind firewall A it looks like
firewall A does not forward the PPP LCP packets.
Am I correct that mutliple GRE (proto 47) tunnels would be a problem when the clients have the same IP address ?
We are running the standard kernel 2.6.9-42.0.3.EL.
Firewall A inside interface:
--snip--
7 1.905608 client server PPTP Outgoing-Call-Request
8 1.910061 server client PPTP Outgoing-Call-Reply
9 1.935465 client server TCP commlinx-avl > pptp [ACK] Seq=325 Ack=189 Win=32120 Len=0
10 2.844911 client server PPTP Set-Link-Info
11 2.909621 client server PPP LCP Configuration Request
12 2.992528 server client TCP pptp > commlinx-avl [ACK] Seq=189 Ack=349 Win=16212 Len=0
13 5.085418 client server PPP LCP Configuration Request
14 7.504568 client server PPP LCP Configuration Request
--snip--
Firewall A outside interface:
--snip--
7 1.905608 firewall A server PPTP Outgoing-Call-Request
8 1.910061 server firewall A PPTP Outgoing-Call-Reply
9 1.935465 firewall A server TCP commlinx-avl > pptp [ACK] Seq=325 Ack=189 Win=32120 Len=0
10 2.844911 firewall A server PPTP Set-Link-Info
11 2.992528 server firewall A TCP pptp > commlinx-avl [ACK] Seq=189 Ack=349 Win=16212 Len=0
--snip--
--
Michael Gale
Red Hat Certified Engineer
Network Administrator
Pason Systems Corp.
