Manually add route to VPN

Question

Hello server enthusiasts,

I have a VPN (pptpd running on Ubuntu 10.04) that I am trying to connect to with a client (Win7).

I can successfully connect to the VPN.

Once connected to the VPN, I can ping both interfaces on the server (1.2.3.4 which is a public IP facing the internet, and the address used to connect to the VPN server (eth0), and 192.168.0.1 (ppp0)).

I cannot ping any other addresses from the Win7 client. IP forwarding is enabled server side.

I am having trouble adding a route via the windows route command.

Server: eth0 - 1.2.3.4 (facing internet), ppp0 - 192.168.0.1

Client: VMware Win7 ppp - 192.168.1.1

Result of ipconfig on Win7 client:

Default Gateway: 0.0.0.0
IP: 192.168.1.1
Subnet: 255.255.255.255

I have tried

route ADD 192.168.0.1 255.255.255.255 192.168.0.1
route ADD 1.2.3.4 255.255.255.255 192.168.0.1
route ADD 192.168.0.1 255.255.255.255 192.168.1.1 METRIC 266

All fail, telling me that

Incorrect argument 192.168.1.1

or

Incorrect argument 192.168.0.1

There are also 2 metrics corresponding to these IP's in the tables that display as a result of route print Which must be used?

I would appreciate if someone could shed light on how to add this particular route.

When adding routes, must I always specify a metric and/or interface? Is there anything unique about adding VPN based routes?

Thank you for reading.

Doesn't look like you know enough about networking to be doing this yourself, honestly. Contact your network admin or helpdesk. — HopelessN00b, Nov 26 '12 at 20:07
Jack, your first sentence indicates to me that you don't fully understand our site. This is not a site for enthusiasts, this is a site for professionals. Your conduct so far has not been that of a professional. — Mark Henderson, Nov 26 '12 at 20:55

HopelessN00b · Answer 1 · 2012-11-26T20:16:13.127

Default Gateway: 0.0.0.0

Your Default Gateway is wrong, try fixing that first. 0.0.0.0 is the any address, and not a valid IP for a host. Basically, your network is configured to shove traffic out to any address, rather than the address it should send its traffic to.

Subnet: 255.255.255.255

This is also wrong. That's the subnet mask for a single host, which is presumably not what you want.

Finally, your syntax for the route add command is all kinds of wrong.

You should be using: route add [destination IP] MASK [destination subnet mask] [IP of gateway used to reach destination IP], but this requires knowing what those terms mean, as well as having some idea about what networks or hosts you need to connect with a route, and it doesn't sound like you do, to be quite honest. As I said in the comments, you seem like you'll need to contact your helpdesk or network administrator to get you through this.

From route /?:

Manipulates network routing tables.

ROUTE [-f] [-p] [-4|-6] command [destination]
                  [MASK netmask]  [gateway] [METRIC metric]  [IF interface]

  -f           Clears the routing tables of all gateway entries.  If this is
               used in conjunction with one of the commands, the tables are
               cleared prior to running the command.

  -p           When used with the ADD command, makes a route persistent across
               boots of the system. By default, routes are not preserved
               when the system is restarted. Ignored for all other commands,
               which always affect the appropriate persistent routes. This
               option is not supported in Windows 95.

  -4           Force using IPv4.

  -6           Force using IPv6.

  command      One of these:
                 PRINT     Prints  a route
                 ADD       Adds    a route
                 DELETE    Deletes a route
                 CHANGE    Modifies an existing route
  destination  Specifies the host.
  MASK         Specifies that the next parameter is the 'netmask' value.
  netmask      Specifies a subnet mask value for this route entry.
               If not specified, it defaults to 255.255.255.255.
  gateway      Specifies gateway.
  interface    the interface number for the specified route.
  METRIC       specifies the metric, ie. cost for the destination.

All symbolic names used for destination are looked up in the network database
file NETWORKS. The symbolic names for gateway are looked up in the host name
database file HOSTS.

If the command is PRINT or DELETE. Destination or gateway can be a wildcard,
(wildcard is specified as a star '*'), or the gateway argument may be omitted.

If Dest contains a * or ?, it is treated as a shell pattern, and only
matching destination routes are printed. The '*' matches any string,
and '?' matches any one char. Examples: 157.*.1, 157.*, 127.*, *224*.

Pattern match is only allowed in PRINT command.
Diagnostic Notes:
    Invalid MASK generates an error, that is when (DEST & MASK) != DEST.
    Example> route ADD 157.0.0.0 MASK 155.0.0.0 157.55.80.1 IF 1
             The route addition failed: The specified mask parameter is invalid.
 (Destination & Mask) != Destination.

@Jack It's really not, but whatever. Good luck with your problem. — HopelessN00b, Nov 27 '12 at 01:40

score 0 · Answer 2 · answered Nov 26 '12 at 19:52

0

In the first example you are telling windows to reach 192.168.0.1 by going to 192.168.0.1...an IP that Windows does not see.

In the third example you are telling windows to reach 192.168.0.1 by going to itself.

I also notice you have no default gateway...therefore Windows only knows himself (192.168.1.1) especially since your subnet is 255.255.255.255.

answered Nov 26 '12 at 19:52

Alex

3,129
21
28

255.255.255.255 is a common VPN sub netting scheme. Google it. – Jack Nov 26 '12 at 20:37
Maybe, but the combination of a 255.255.255.255 subnet and no default gateway makes your workstation quite alone on your network – Alex Nov 26 '12 at 20:41
Not if that network interface is bridged to another interface, (the standard VMWare one...) that's already facing the internet... (hence how this is possible) – Jack Nov 26 '12 at 20:48

Manually add route to VPN

2 Answers2