I have an old computer in my dorm room. It acts as a gateway and traffic-shaper (htb) for me and my roommates.
Debian is installed into it. It has been working quite good for a year. Nothing happened until Thursday. 2 days ago it started behaving unexpectedly.
We have 2 interfaces:
- **eth0** - this one looks into local network.
- **ppp0** - this one connects with internet.
We have configured NAT.
The strange fact here is that server suddenly becomes unreacheable.
ifconfig shows, that eth0 and ppp0 are both up.
But I can't ping server from my laptop as well as laptop from server.
But ppp0 works! I can ping google.com from server.
ifconfig eth0 down
eth0 and ppp0 go down. only lo is up. As expected
ifconfig eth0 up
Server becomes reachable.
Then I try to pon dsl-provider ... and it doesn't start PPPoE connection.
Only reboot makes it work... just for 5-7 minutes.