Updating to Kernel 2.6 breaks DNS resolving

[movEAX_444]

Slackware 10.1, 2.4.29 worked fine, but after updating to 2.6.10.12, I can not longer access the internet. I think that I can access sites by IP but not by name. Links / lynx hangs at "Looking for host..."

What gives?

[Gogeta_44]

Can you ping ip addresses and not domain names? If so, you need to look in /etc/resolv.conf to make sure that your dns hosts are listed. Just because lynx hangs at "looking for host" doesn't mean it's specifically a dns problem. Make sure you have the modules for your network card loaded using the command "lsmod" and make sure that all network devices needed are listed and have ip addresses when you type the command "ifconfig". If you have a router and it uses dhcp, check to see if you have your dhcp client running (dhcpcd on slackware). If you used a different configuration for your new kernel, chances are that it didn't have the correct ethernet drivers compiled in or compiled as modules.

[je_fro]

Did you compile the kernel yourself? Did you forget to include IPV4 or some other trivial package?

[movEAX_444]

What is the name of the IPV4 option in .config? I'm sure I am doing something dumb.

/etc/resolve.conf is correct. I can access my router's setup page but not any remote site. I will try pinging by IP and hostname tomorrow.


--------- EDIT -----------
The problem has been fixed. I don't know what caused it, but I reset power cycled the modem and router and now it works fine. Thanks for the replies.

[error27]

If it breaks again check whether you have ECN disabled.

[ ] IP: TCP Explicit Congestion Notification support

In the .config it looks like:
# CONFIG_INET_ECN is not set

[bwkaz]

Or disable it at runtime:

echo "0" >/proc/sys/net/ipv4/tcp_ecn