Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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I'm hoping this is an easy one for somebody out there...
I have a RedHat 6.2 server that has recently been connected to the outside world. The server was initially installed with a bogus gateway from a different subnet than what they are currently on. Now that we have a firewall in place I need to change the gateway.
I run linuxconf and change the default gateway. I reboot the server. I can ping the server from another machine but cannot ping out from the server. Not even to any machines on the LAN. I try to telnet into the machine and the session fails to connect. I run the route command and it hangs for a couple if minutes and finally gives me some output. It looks like it took the settings but something is getting screwed up in the process.
The /etc/sysconfig/network file looks fine and has the gateway defined.
The only way I can make it work again is by changing the default gateway back to the original IP address.
There is only one adapter on the machine.
I have found some info on the web about this but I must be missing something.
What do you get when you run the command 'route'? BTW A console command to change default gateway is:
route del default
route add default gw your_gateway_here
When the I run 'route' with the non working gateway in place, this is what I get:
[root@creek_linux /sbin]# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
192.168.1.51 * 255.255.255.255 UH 0 0 0 eth0
192.168.1.0 * 255.255.255.0 U 0 0 0 eth0
127.0.0.0 * 255.0.0.0 U 0 0 0 lo
[root@creek_linux /sbin]#
When I put the new gateway in place, it hangs at:
Destination Gateway Genmask Flags Metric Ref Use Iface
for about 2 minutes then gives me the rest of the output including the new line with the default gateway.
(I can't get the exact line that it outputs right now)
I tried using the commands that you said when I was troubleshooting earlier. Whenever I monkey'd with the gateway though is when everything stopped working.
You will see that the gateway is currently set up wrong. The gateway address is 192.168.37.5 and it should be 192.168.1.1. When I change this address or even change the network file to reference the correct gateway device, it hoses the machine and no one can connect. Here is the output you requested:
I have tried that and as soon as I do, it messes up the networking. Anytime I add or change a gateway in any shape or form, it kills networking. Do you think it could be driver related?
"I have a RedHat 6.2 server that has recently been connected to the outside world. The server was initially installed with a bogus gateway from a different subnet than what they are currently on. Now that we have a firewall in place I need to change the gateway.
I run linuxconf and change the default gateway. I reboot the server. I can ping the server from another machine but cannot ping out from the server. Not even to any machines on the LAN. I try to telnet into the machine and the session fails to connect. I run the route command and it hangs for a couple if minutes and finally gives me some output. It looks like it took the settings but something is getting screwed up in the process.
The /etc/sysconfig/network file looks fine and has the gateway defined.
The only way I can make it work again is by changing the default gateway back to the original IP address.
There is only one adapter on the machine."
It messes it up by killing TCP/IP in some way. I'm not at the location of the server right now, but when I do change the gateway to be correct, it shows up in the routes eventually (2 minutes). Everything looks perfect but can't ping out and can't connect to it via telnet. I'm beginning to think that it's a lost cause...
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