DNS resolve very slow in Fedora 17 KDE spin

[JClosed]

I downloaded and installed the KDE version of Fedora 17.

Everything works great exept... browsing in Firefox (and any other browser) is slow as hell. Resolving a page takes about 10 to 20 seconds, which is far too slow for a normal use.

I am using Debian in dual boot, and here DNS resolving with exactly the same settings is as fast as to be expected (fraction of seconds). So - no hardware or general settings problem. This is really a Fedora 17 problem as far as I can see.

Now I did all the "standard" workarounds known to me, like:

Set network.dns.disable ipv6 to true in Firefox - no result

Turn off ipv6 in the network card settings - no result

Do the following:
echo -e "install ipv6 /bin/true\nblacklist ipv6" > /etc/modprobe.d/blacklist-ipv6.conf
service ip6tables stop
chkconfig ip6tables off
And then reboot

Still browsing (dns resolving) stays slow. I am out of ideas. Anyone has the same problems?

And secondly - another problem. I use the Midnight Commander (mc) a lot on my systems. I run this in the terminal (Konsole), but I notice it can take several seconds to start mc (typically about 10 to 15 seconds). I never had this slow start in any other Linux version. Normally mc should start instantly without any delay.. Very strange.

Now I think about it - Firefox also takes several seconds to just start up. Much slower than in Debian and Kubuntu.

Could this be related in some way?

[rtguille]

>And secondly - another problem. I use the Midnight Commander (mc) a lot on my systems. I run this
>in the terminal (Konsole), but I notice it can take several seconds to start mc (typically about 10 to 15
> seconds). I never had this slow start in any other Linux version. Normally mc should start instantly
> without any delay.. Very strange.

I found this ridiculous, sometimes i had to disable the network connection just to let mc start and drop
such "pause" looking "for what" at startup, i think it is more that 15 seconds... For what reason is mc
trying to resolve anything.

As for the slow dns behaviour, in my case, i sometimes need to use google's dns for updates/curl because
my router's openwag200g dns and my isp produces a lot of curl -6 bla bla bla, being unable to resolve any
mirror....


Cheers.

[JClosed]

Yep - if I only had a clue what is happening.

I looked trough several log files (in /var/log) but did not see anything that caches the eye. Now I must admit I am no developer, so it is easy to miss things that are obvious for others...

Anyway - there is definitely something fishy going on in the network settings. As I said - with exactly the same settings Debian or Unbuntu (and KUbiuntu) run without any problem or slow dns resolving. Unfortunately -as I said- so far I have no clue what is going on, and have no idea what to do to make things more bearable.

This problem has to be resolved before I can really use Fedora. I must say I am a bit dissapointed so far. That's a shame, because I think Fedora is generally a good distro.

Next thing to try, is to find out if this is a KDE only thingy. I am going to install the GNOME spin, an see if the same problems pop up.

I keep everyone informed...

[Dcookie]

In my case, it was just Firefox (18) that was slow. I got "Looking up xxxxx" messages that hung for a few seconds each. I used the first two suggestions on this page: http://forums.fedoraforum.org/showthread.php?t=42943, but that didn't help much. I finally discovered an add on in FF (ITunes Application Detector) that when disabled has seemingly caused the problem to disappear. I don't use ITunes, don't know where the add-on came from.

[marko]

The usual thing that fixes slow dns particular to Firefox is:


Use "about:config" in the location bar
<hit the "I'll be careful" checkbox if it shows>
use the search tool with "ipv6"

select network.dns.disableIPv6 and hit it with the right mouse button and select "Toggle"

the network.dns.disableIPv6 value should now be true. Leave the 'about:config' tab and it should be faster to access pages.

[gadgetwiz]

Try OpenDNS or some other public DNS. I've experienced the same symptoms ("looking up ...") as you've described and using OpenDNS has always fixed it.