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Linux Victim
Hello.
I've been having some strange internet problems lately. Here's what happens:
1.) The internet dies. (Duh)
2.) After waiting for a while, hoping it's an ISP problem, I see that it's either my modem or my Linux router. I can fix this in one of two possible ways:
a) Turn the modem off and back on again. If that doesn't work...
b ) Reset the router

While I'm thankful I can temporarily remedy the situation, it's really getting annoying. I don't even know where the problem lies! The modem? One of the ethernet cards? The software? I'm stumped.
I'm using RH 9.0 on a PII 266 with 98 MB RAM.
Any help is greatly appreciated!
hughesjr
The Modem (is it a cable or DSL connection ... if DSL, do you use PPPOE) usually has lights for connection, send, recieve and activity .... are the lights like they normally are when you have the problem?

The router also has a connection light ... is it normal.

Some worms (or multiple port scans) cause problems with some modems/routers ... what is the manufacturer/model number of the router and the modem?
Linux Victim
I have a cable connection. Sorry, should've mentioned that sooner... Yes, the lights blink normally as if nothing was wrong. I use this modem:

Can't find the manual right now, I know it's around here somewhere... I think it's called "RCA Thompson DOCSIS Two-Way Modem". Sounds about right. My router is a computer running RedHatLinux 9.0 on a Pentium II 266 MHz with 98 Megs of RAM. My connection is like this, roughly:

ISP -> My modem -> My router (RH 9.0) -> Switch -> The computers in my house

Something like that, anyway.
hughesjr
If your router is using DHCP as the address, you might be having the DHCP lease time out and not renewing the lease .... try issuing the command:

/etc/init.d/network restart

(as the root user on the Linux router) ... and see if that fixes the problem.
Linux Victim
Thanks for the tip. If this really is the case, is there a way to fix this permanently, like writing in a script somewhere that it should keep trying if it times out? I'll get back to you whether this works or not as soon as my internet crashes again, which shouldn't be too far in the future... sad.gif
hughesjr
If that fixes it, you may need to write a script to renew the IP address ... which we can do.
Linux Victim
Well, there it was again. I did as you advised me to and here's what happened:
CODE
[root@rogga init.d]# ./network restart
Shutting down interface eth0:                              [  OK  ]
Shutting down interface eth1:                              [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Setting network parameters:                                [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface eth0:
Determining IP information for eth0...PING 213.143.84.1 (213.143.84.1) 56(84) bytes of data.

--- 213.143.84.1 ping statistics ---
10 packets transmitted, 0 received, 100% packet loss, time 9014ms

failed.
                                                          [FAILED]
Bringing up interface eth1:                                [  OK  ]
[root@rogga init.d]#

I noticed it took quite some time for Linux to shut down eth1. Maybe that's the problem? Anyway, I did this three times in a row, with no success. Then I tried unplugging the modem and plugging it back in again and tried the same thing as above. Now it was:
CODE
[root@rogga init.d]# ./network restart
Shutting down interface eth1:                              [  OK  ]
Shutting down loopback interface:                          [  OK  ]
Setting network parameters:                                [  OK  ]
Bringing up loopback interface:                            [  OK  ]
Bringing up interface eth0:                                [  OK  ]
Bringing up interface eth1:                                [  OK  ]
[root@rogga init.d]#

Problem solved? Not quite. I was still offline. Only after typing "reboot" via SSH did I come back online after a few moments. So, any idea what the problem could be?
hughesjr
After rebooting the modem ... did you first wait for the all the lights to show a normal connection state before you reran the /etc/init.d/network restart command? (On my machine, the top 3 lights blink intermittently for 20-60 seconds while establishing a connection to the ISP, downloading the config file, and setting up the modem parameters ... then those lights turn solid and a bottom activity light starts blinking ... and after that, I can request an IP address).
Linux Victim
Yes, I always wait for the lights to go back to normal.
hughesjr
The next time it's broke, try logging on to the redhat box and pinging something outside you network (like www.yahoo.com) .... maybe restart iptables (/etc/init.d/iptables restart) ... (or if you are using a seperate firewall script ... do the command:

iptables -F

and then rerun your firewall start script.
Linux Victim
I tried pinging before already. It said something like "Destination Network could not be reached". And thanks for the advice, I'll try restarting the firewall script the next time it goes crazy on me.
Linux Victim
Tried that too. no dice. This is really starting to get to me. The fact that I don't know what the hell is wrong with my router is the most irritating thing of all! It could be anything from the ethernet card to the linux software! If I knew what was wrong I could at least replace it.
hughesjr
I think I would try installing a different linux distro for the firewall .... are you using a program for the firewall that only runs on redhat 9?
Linux Victim
No, I'm using an IPtables firewall script I got from this site. I modfied it to my needs of course. I opened a few ports for P2P programs and removed this line:

CODE
# This rule protects your fowarding rule.
$IPT -A FORWARD -i $INT -m state --state NEW,INVALID -j DROP
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