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Re: [linux-tr] communication outside subnet

As Carsten Brink said:
> I hope someone can help me or explain what commands are actually carried
> out during the =93cure=94-process described. Knowing the commands might h=
> elp
> locating the solution.
> Thank you in advance,
> 		Carsten Brink
It sounds like some process (automated?) is removing your default gateway
from the routing table.

When IP is working fine, run this command:  netstat -rn

You'll see something like:

Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface   U      2000 0          0 tr0       U      3584 0          0 lo         UG      576 0          0 tr0

Here, my tr0 card is, and is therefore on the
network. With the first entry, I shoul be able to being any IP address on
my local subnet.

The second entry is the loopback interface. We'll ignore it.

The 3rd entry is the default gateay, This entry in my
routing table tells me how to get to IP hosts off of my local subnet.

When your routing fails, first ping your default gateway. Then run 'netstat
-rn' again.

If you can ping your gateway and your routing table doesn't have the entry, then some program is messing up your routing table.

If you cannot ping your gateway, then your router is going up and down all
the time. I doubt that this is the case.

To fix your defaulte route manually,:

route add default gw metric 1

(of course, is *my* default gateway. Put in the IP address
of your gateway.)


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