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VPN question - "error 721: Remote computer did not respond"

I'm trying to setup VPN against a Windows 2003 server. Client is XP pro. The server is behind a router that run NAT.
When I'm connecting to the VPN server directly to the internal IP I connnect without problems.
Our ISP have setup the NAT on the router to temporarily allow all IP traffic to this external IP.
But when I try to VPN connect to external IP it hangs with message "verifying username/password" and then I get "error 721: Remote computer did not respond".

Any ideas what might be wrong?

Are any particular settings on the router needed to make this work?

ASKER CERTIFIED SOLUTION

Steve McCarthy, MCSE, MCSA, MCP x8, Network+, i-Net+, A+, CIWA, CCNA, FDLE FCIC, HIPAA Security Officer

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rj2

ASKER

Well, the ISP says that they believe everything is ok on the router, and it is setup according to the url below.
http://cisco.com/en/US/tech/tk827/tk369/technologies_configuration_example09186a00800949c0.shtml

So if this problem is on the server, how do I fix it?

Could setting up RADIUS help?

SOLUTION

mikeleebrla

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Steve McCarthy, MCSE, MCSA, MCP x8, Network+, i-Net+, A+, CIWA, CCNA, FDLE FCIC, HIPAA Security Officer

I think setting up Radius will only overcomplicate things. If you can connect internally, then your server is setup correctly. What is the address of the server. I don't believe your port forwarding is correct or GRE is not enabled.

SOLUTION

pcavenue

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rj2

ASKER

The router is a Cisco 1721.
Is "ip nat inside source static tcp 10.0.1.8 x.y.z.58 extendable" enough to make GRE pass through, or is something else needed?

rj2

ASKER

Output from "sh ip nat translations" below.
External servcer ip replaced with serverip
My external ip replaced with myip.

>sh ip nat translations
Pro Inside global Inside local Outside local Outside global
tcp serveripx.serveripy.serveripz.58:1723 10.0.1.8:1723 myipx.myipy.myipz.170:2689 myipx.myipy.myipz.170:2689
tcp serveripx.serveripy.serveripz.58:1723 10.0.1.8:1723 myipx.myipy.myipz.170:2690 myipx.myipy.myipz.170:2690
gre serveripx.serveripy.serveripz.58:256 10.0.1.8:256 myipx.myipy.myipz.170:256 myipx.myipy.myipz.170:256
gre serveripx.serveripy.serveripz.58:29012 10.0.1.8:29012 myipx.myipy.myipz.170:29012 myipx.myipy.myipz.170:29012
gre serveripx.serveripy.serveripz.58:1423 10.0.1.8:1423 myipx.myipy.myipz.170:1423 myipx.myipy.myipz.170:1423
tcp serveripx.serveripy.serveripz.58:1723 10.0.1.8:1723 --- ---
gre serveripx.serveripy.serveripz.58:512 10.0.1.8:512 myipx.myipy.myipz.170:512 myipx.myipy.myipz.170:512

What could be wrong?
Is the problem on the router or on the VPN server? The VPN server works when I connect directly to it (to ip 10.0.1.8)

rj2

ASKER

Also, when I run command netstat on the VPN server when I try tp connect, I see a "servername:pptp" connection as "established".

The VPN server (2003 server) is member of a domain, with another 2003 server as the domain controller

rj2

ASKER

I compared Etheral output when I connect directly to internal IP and to external IP.
When I connect directly to external IP there is much more PPP traffic compared to when I connect to external IP.

PPP LCP Configuration Request
PPP LCP Configuration Request
PPP LCP Configuration Ack
PPP LCP Configuration Reject
PPP LCP Configuration Request
PPP LCP Configuration Nak
PPP LCP Configuration Request
PPP LCP Configuration Ack
PPP LCP Identification
PPP LCP Identification
PPTP Set-Link-Info
PPTP Set-Link-Info
PPP CHAP Challenge
PPP CHAP Response
PPP CHAP Success
PPP CBCP Callback Request
PPP CBCP Callback Response
PPP CBCP Callback Ack
PPP CCP Configuration Request
PPP IPCP Configuration Request
PPP CCP Configuration Request
PPP IPCP Configuration Request
PPP CCP Configuration Nak
PPP CCP Configuration Nak
PPP IPCP Configuration Ack
PPP CCP Configuration Request
PPP IPCP Configuration Reject
PPP CCP Configuration Request
PPP IPCP Configuration Request
PPP CCP Configuration Ack
PPP CCP Configuration Ack
PPP IPCP Configuration Nak
PPP IPCP Configuration Request
PPP IPCP Configuration Ack

When it fails to external IP there is only one PPP package from me to server
PPP LCP Configuration Request
TCP pptp > 4930
PPP LCP Configuration Request
PPP LCP Configuration Request
PPP LCP Configuration Request
PPP LCP Configuration Request
PPP LCP Configuration Request
PPP LCP Configuration Request
PPP LCP Configuration Request
PPP LCP Configuration Request
PPP LCP Configuration Request
PPTP Call-Clear-Request
PPTP Call-Disconnect-Notify
PPTP Stop-Control-Connection-Reques
PPTP Stop-Control-Connection-Reply

Does this help anything im finding out how to fix this?

rj2

ASKER

Hello!
I have been able to make this work now by setting it up on another router. Our ISP was not able to make this work.

Steve McCarthy, MCSE, MCSA, MCP x8, Network+, i-Net+, A+, CIWA, CCNA, FDLE FCIC, HIPAA Security Officer

Glad to hear...... Thanks and good luck!

VPN question - &quot;error 721: Remote computer did not respond&quot;

VPN question - "error 721: Remote computer did not respond"