Alright This problem might just be just my own misunderstanding of how ip's and subnets work, but i still can't get it resolved.

Heres my situation.

I've got a slackware bawx set up as a firewall running ip-masq. Everything worked fine for over a year. Last year our ip settings were as follows

eth0:

ip: 137.85.35.47
netmask: 255.255.0.0
gateway: 137.85.1.1

eth1:

ip: 192.168.0.1
netmask: 255.255.255.0


Everything was working fine UNTIL the IT Dept. notified our dorm that the subnet was going to change from 255.255.0.0 to 255.255.224.0

When i changed from .0 to .224 I can still ping other people in the dorm.. so all my equipment still works, but when i try to ping 137.85.1.1 i get Network Unreachable

when I run /etc/rc.d/rc.inet1

SIOCADDRT: File exists
Configuring eth0:
ifconfig eth0 137.85.35.42 broadcast 137.85.63.255 netmask 255.255.224.0
Configuring eth1:
ifconfig eth1 192.168.0.1 broadcast 192.168.0.255 netmask 255.255.255.0
SIOCADDRT: Network is unreachable

i do a route -n and i get

route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.0.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
137.85.32.0 0.0.0.0 255.255.224.0 U 0 0 0 eth0
127.0.0.0 0.0.0.0 255.0.0.0 U 0 0 0 lo


i tried to do a
route add -net default gw 137.85.1.1 netmask 0.0.0.0 metric 1 eth0

which produces

SIOCADDRT: Network is unreachable

So to sum it up:

-All my equipment/cables are functional
-All windows machines on the network use the 255.255.224.0 netmask without problems
-I've tried without success on my slack box, a gentoo box, a knoppix live cd, a gentoo live cd, and another slackware box. ALL of which produce the same results
-I can still ping other machines on the LAN


Any help is appreciated on this one. Thanks


Scorchen

Sure you can't reach the gateway. Netmask 255.255.224.0 translates to /19 (I prefere that notation.) This means there are 2^(32-19)=8192 IP addresses on your network:

Your IP/netmask is 137.85.35.47/19 so the network includes the IP range 137.85.32.0-137.85.63.255 and 137.85.1.1 is not in that range.

So, somethings wrong. If you are really supposed to use the gateway 137.85.1.1 you can add a route to this host like so:

route add -host default gw 137.85.1.1 eth0

and then hope that your IP packets hit a bridge that knows about the other network or you ask your IT guys for a gateway that's actually in your network.

Hey thanks.. Any ideas as to why all the windows machines don't have a problem?

Dunno. Maybe when you enter the gateway in the windows networking config thing it doesn't care about the netmask which would be the equivalent of using the -host option to route. Or maybe there's some proprietary vodoo going on.