VPN setup for PPTP

G

Guest

I am having difficulty when trying to authenticate to the VPN server we have
configured.
I have configured the required Remote Access Policy in RRAS; I try to
connect each time and I get " Verifying username and password", but I am
never authenticated and the VPN connection never establishes.
The Server Status in RRAS is UP. The PPTP and L2TP ports all show Inactive.
I have "Grant Access" selected in the Remote Access Policy.
Any suggestions would be welcome.
Thank You.
 
R

Robert L [MS-MVP]

Assuming you receive the error 800, you may want to check the status of IP port 47 (GRE).

Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
I am having difficulty when trying to authenticate to the VPN server we have
configured.
I have configured the required Remote Access Policy in RRAS; I try to
connect each time and I get " Verifying username and password", but I am
never authenticated and the VPN connection never establishes.
The Server Status in RRAS is UP. The PPTP and L2TP ports all show Inactive.
I have "Grant Access" selected in the Remote Access Policy.
Any suggestions would be welcome.
Thank You.
 
G

Guest

Please help me understand why. Does PPTP use GRE encapsulation??

Thanks Robert...

Kevin
 
R

Robert L [MS-MVP]

Yes, PPTP does need GRE.

VPN Setup
A: PPTP VPN uses TCP Port 1723, IP Protocol 47 (GRE); L2TP: UDP Port 1701; IPSec:
UDP Port 500, Pass IP protocol 50 and 51. Note: 47 is a protocol number ....
www.chicagotech.net/vpnsetup.htm

ports for vpn
Don't have IP protocol 47 (GRE) Port 42 for name resolution. Don't have IP protocol
47 (GRE). A PPTP connection will fail if the firewall/router blocks GRE, ....
www.chicagotech.net/portsforvpn.htm


Bob Lin, MS-MVP, MCSE & CNE
Networking, Internet, Routing, VPN Troubleshooting on http://www.ChicagoTech.net
How to Setup Windows, Network, VPN & Remote Access on http://www.HowToNetworking.com
Please help me understand why. Does PPTP use GRE encapsulation??

Thanks Robert...

Kevin
 
B

Bill Grant

A PPTP connection cannot work if GRE is blocked. PPTP only handles the
setup and maintenance of the tunnel. The actual data is encrypted and
encapsulated. The encapsulation uses a modified GRE header. If GRE is
blocked, no data is transferred and the connection closes.
 

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