iptables firewall stops working properly

[whmicro]

Hello:

I wrote an iptables script and ran it. Everything seems to be working fine. When I leave the box turned on overnight (the way is supposed to be) the next day I can't browse the Internet. I can do everything else: ping, traceroute, and even chat through yahoo messenger, but not browse the Internet. I don't know what may be causing this problem.

If I reboot the box and power-cycle the cable modem (RR) everything goes back to normal. But again, if I leave and come back hours later, I can't browse the Internet.

In case is a DHCP problem, I have a couple of chains that will allow the DHCP server to renew the lease. But the same problem persist.

I am running:
RH 7.2
and turned off power management on the bios.

Thanks in advance for your help.

 

[fluid11]

You say that you can't browse the internet, but you can ping and do everything else on the internet? Can you ping hostnames on the internet? Can you view websites using the IP address? Maybe it is a DNS issue.

ChrisP

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[whmicro]

Is not a DNS issue. If I 'ping yahoo.com' it works from anywhere in the network. When the box is freshly rebooted I can do everything but after hours of inactivity I can't browse the Internet.

 

[fluid11]

After these "hours of inactivity", can you still ping yahoo.com by hostname? If you can, can you connect to the website using its IP address, rather than the hostname?

ChrisP ------------------------------------------------------------------------------
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[whmicro]

After the "hours of inactivity" I can still ping yahoo.com and do everything else but, browse the Internet (even if I enter the ip address on the browser Address bar.

This is a very weird problem, I've searched the web regarding this and the only thing closer is a dhcp lease renewal problem which I take care of in the script by allowing the dhcp server to communicate freely with the firewall through ports 67 and 68.

Today, I upgraded iptables from 1.2.3 to 1.2.4. Let's see what this might do.

I can't think of any other thing to do to the box.

Thanks.

 

[fluid11]

What is the error message in the web browser? Time out? Can't find page?

What happens if you manually renew the DHCP lease?

dhcpcd -B -n


ChrisP ------------------------------------------------------------------------------
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[whmicro]

I haven't tried yet. I'll try now.
Looks like it ran the script but, I don't see any differences on the dhcpcd-ethx.info file. Leasetime, Renewaltime, and rebindtime are still the same values or times.

I don't get any errors on the browser. On the status bar says Website found... Waiting for response and it stays there forever.