[email protected] wrote:

> And I can't understand what is slowing DNS activity (connections by naame 
> are slow while connections by IP are normal).

Look at your name resolver setup. Slow DNS resolution is more likely to be an 
issue with DNS than with the firewall - ie randomly blocking stuff isn't likely 
to help.

So first off, what is doing DNS resolution for you/your devices ?
Is the issue consistent ?
Have you used a packet sniffer (eg wireshark, others are available) to sniff 
for DNS packets ? Eg, "tshark -i eth0 -f 'port 53'" will show you DNS packets 
on eth0.

For example, if you have a resolver configured in teh client that isn't 
actually working, then you'll get slow DNS lookups. The resolver library may 
well work through the list, and if the first one doesn't work then it won't 
move on to the next until the first has timed out. Thus all your DNS lookups 
are "slow". This behaviour varies widely between OSs and setups - eg I think 
Windows (at least some versions) will drop a "dead" resolver to the bottom of 
it's list and only look at it again if all the rest fail.


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