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Can't talk between VPN'd client and Linux server.

Hello,

I have two Linux servers running the latest AS Redhat.

My VPN server is a basic Windows 2003 machine, supporting pptp, (I don't have certificate installed yet for l2tp)

Client machine is Windows XP.

All patches/updates have been applied to all machines.

These machines are all running on the same departmental level subnet.

Client attaches to VPN without issue, makes pptp connection, and I can see all windows based resources on the local network. I can ping other windows machines, I can connect to shares, I can access web pages which are ordinarily blocked by the firewall...

With the exception of my two Linux machines.

From my VPN machine, I can ping/connect to the web services/ssh to the

two linux machines, I can do the same from any local windows client.

From the linux machine, I can ping all the local windows

servers/clients.

However, I cannot ping the VPN client from the linux machines (I can ping, and as I write this, I am connected to the VPN client via remote desktop, from this local machine), nor can I pull up the web page hosted on the linux machine.

Now here it gets even worse.

If I connect to the main campus VPN connection, then I CAN see the web page hosted on the linux machines (I cannot ping though, as ICMP is blocked at our department firewall...)

Any help would be greatly appreciated!!

Reply to
thenighthawk
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This forum is for Windows Firewall Discussion. You may wish to post this to microsoft.public.win2000.networking.

And to try to be of help, you may want to sniff on the Linux servers, see if they are even getting the packets from the VPN client. Your entire setup is not clear, and you may be experiencing a simple route issue ( if the Linux boxes don't know where to send packets to the VPN client's subnet etc. ) A sniff of a simple PING should help you determine where to look. Post back in the appropriate forum and I'll try to help more.

Reply to
Dusty Harper {MS}

Unfortunately there's no routing being done by the Linux boxes at all, they are on the private side of the VPN Server's network (both physically and logically).

Reply to
thenighthawk

They still need to perform a route lookup to see which router to send the traffic ( unless the VPN client is handed an IP on the locl subnet )

Reply to
Dusty Harper {MS}

That is the case, the VPN client gets an address from within the local subnet.

Once the VPN client is connected, I can remote desktop to the client using the local address, the client can see all my windows boxes, but these two linux boxes are invisible, I can't ping, ssh, ftp, or pull up the web page, whether I try to do so using the IP address of the linux box, or the name.

I am at such a loss as to why all the windows machines are visible, but the linux are not.

Dusty Harper {MS} wrote:

Reply to
thenighthawk

Mike, you were on the right track!

Monitoring the ARP caches, the Linux boxes were trying to communicate with the public side IP address (also on my local subnet, as I am not able to do NAT and private addressing here).

I used the default filter to block all but VPN tunnel traffic on the public address. By adding my local subnet in the "allow" for incoming packets to the public side address, all was well.

Thanks!!

Mike Drechsler - SPAM PROTECTED EMAIL wrote:

Reply to
thenighthawk

What does the arp table on the linux box look like? The arp address of the VPN clients IP should resolve to the same ethernet id as the VPN gateway/server. Also what does the arp table on the client look like. Does it get the ethernet id of the linux box. If you find arp problems, does creating a static entry with the ethernet mac address of the remote system help?

Reply to
Mike Drechsler - SPAM PROTECTE

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