Help: machines on subnet can't ping the machines outside subnet

Help: machines on subnet can't ping the machines outside subnet

Post by Tsung-i Hua » Thu, 12 Jan 1995 06:09:53

  I set up a linux box (running 1.1.75, 2 NE2000 cards) as a gateway of a
subnet.  One ethernet card connects to subnetwork and the other connects to
backbone.  My problem is the machines on the subnetwork cannot ping the outside
world.  I can ping the machines on the subnetwork and the outside world from
this linux box.  The kernel is compiled with IP_FORWARD option on.  And there's
no routed/gated running.  Here are "rc.inet1" and the result of "netstat -nr".

# rc.inted1:
/sbin/ifconfig lo
/sbin/route add


/sbin/ifconfig eth0 ${IP} broadcast ${BROADCAST} netmask ${NETMASK}
/sbin/ifconfig eth1 ${SUBIP} broadcast ${SUBCAST} netmask ${SUBMASK}
/sbin/route add -net ${NETWORK} netmask ${NETMASK} gw ${IP} metric 1 dev eth0
/sbin/route add default gw ${GATEWAY} metric 1 dev eth0
/sbin/route add -net ${SUBNET} netmask ${SUBMASK} gw ${SUBIP} metric 0 dev eth1
# End of rc.inet1

# netstat -nr
Kernel routing table
Destination     Gateway         Genmask         Flags Metric Ref Use    Iface UH    0      0        1 lo   U     0      0       24 eth1     U     0      0       76 eth0         UG    0      0      215 eth0

Any suggestion will be appreciated.


1. can't ping outside subnet

I have a cable modem connected to eth0 with a static IP and domain
name.  When I boot the machine, I can ping any machine on my subnet
but not outside.  If I then run netcfg as root, and leave all the info
unchanged, and just click 'SAVE', I get the message to the terminal:

  SIOCDELRT: No such process

After that, I can access the ethernet normally for the rest of the
time the computer is up, but when I reboot, the same thing happens.

The contents of /etc/sysconfig/network and any other config files that
I can think of remain unchanged.  There is no message sent to
/var/log/messages when I do the 'SAVE' thing in netcfg.

This happens every time.

Any thoughts?

RHL 7.1

John Hunter

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