[K12OSN] OT - Linux router - I'm stuck <-long

Tim Litwiller tim at litwiller.net
Tue Mar 30 07:05:32 UTC 2004


Christopher K. Johnson wrote:

> Tim,
> What interface is used makes no difference.  Whether the interface 
> used has the correct subnet, and whether the correct routes are 
> configured is what matters.  You already verified that ip forwarding 
> is on.
>
> I found it too difficult to decipher what the connectivity and routing 
> configuration were from the original information.
>
> Take another shot at describing your situation:
> Please state the system names and provide the output of 'route -n' for 
> each of the systems involved.
> It would also help if you document connectivity, for example "system1 
> eth0 connects to system2 eth1", etc.
> The output of 'iptables -vnL -t filter' and 'iptable -vnL -t nat' for 
> each system would be helpful to make sure there is no filtering or 
> natting causing the problem.
> Then restate what pinging fails using the system names and interfaces 
> you have just documented.
> Hopefully we can help you with the above information.
>
> Chris
>
ok here is the info you asked for:   from the machines that show the problem

iptables is not installed on any of the machines so iptables or iptable 
has no output
high school router can ping to middle school and district office
middle school router can ping high school and district office - 
computers on middle school network can see
servers on high school network - via ip address
district office router can ping middle school router but no middle 
school network computer or highschool computers

middle school router
route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.0.0.0        0.0.0.0         255.255.255.0   U     0      0        0 eth1
172.16.64.0     10.0.1.102      255.255.224.0   UG    0      0        0 eth2
172.16.96.0     10.0.0.2        255.255.224.0   UG    0      0        0 eth1
172.16.0.0      10.0.1.102      255.255.224.0   UG    0      0        0 eth2
172.16.32.0     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
0.0.0.0         10.0.1.102      0.0.0.0         UG    0      0        0 eth2


eth0      inet addr:172.16.32.254  Bcast:172.16.63.255  Mask:255.255.224.0
connects to middle school lan

eth1      inet addr:10.0.0.102  Bcast:10.0.0.255  Mask:255.255.255.0
connects to radio link to district office   

eth2      inet addr:10.0.1.2  Bcast:10.0.0.255  Mask:255.255.255.0
connects to radio link to high school        


#ip route show
10.0.0.0/24 dev eth1  scope link 
172.16.64.0/19 via 10.0.1.102 dev eth2 
172.16.96.0/19 via 10.0.0.2 dev eth1 
172.16.0.0/19 via 10.0.1.102 dev eth2 
172.16.32.0/19 dev eth0  scope link 
127.0.0.0/8 dev lo  scope link 
default via 10.0.1.102 dev eth2 




district office router
#route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.0.0.0        0.0.0.0         255.255.255.0   U     0      0        0 eth0
172.16.64.0     10.0.0.102      255.255.224.0   UG    0      0        0 eth0
172.16.96.0     0.0.0.0         255.255.224.0   U     0      0        0 eth1
172.16.0.0      10.0.0.102      255.255.224.0   UG    0      0        0 eth0
172.16.32.0     10.0.0.102      255.255.224.0   UG    0      0        0 eth0
169.254.0.0     0.0.0.0         255.255.0.0     U     0      0        0 eth1
127.0.0.0       0.0.0.0         255.0.0.0       U     0      0        0 lo
0.0.0.0         10.0.0.102      0.0.0.0         UG    0      0        0 eth0

#ifconfig
eth0     inet addr:10.0.0.2  Bcast:10.0.0.255  Mask:255.255.255.0
connects to radio link to middle school

eth1	  inet addr:172.16.96.1  Bcast:172.16.96.255  Mask:255.255.224.0
connects to district office network

#ip route show
10.0.0.0/24 dev eth0  scope link 
172.16.64.0/19 via 10.0.0.102 dev eth0 
172.16.96.0/19 dev eth1  scope link 
172.16.0.0/19 via 10.0.0.102 dev eth0 
172.16.32.0/19 via 10.0.0.102 dev eth0 
127.0.0.0/8 dev lo  scope link 
default via 10.0.0.102 dev eth0 









More information about the K12OSN mailing list