Start from clean installation - installing comodo firewall and run browser.
Few second later i have comunicate from firewall that svhost try to cumunicate with first and second dns serwer. I agree, comodo remember my answer and grant (udp) access to dns server.
Few week later (that mean today), i have another communicate that svhost try to communicate with dns first and second server (udp). Well wtf ??? in my list i have green light for it - why commodo ask me again ?
Do you have a router to which you can connect more than 1 PC? If yes, did the 2d alert have the same local address? It could simply be that for whichever reason, your PC adddress has become ***2 instead of ***1 hence the alert from the FW.
One second my ip adress after clean install was 192.168.1.100 - from 30.03.2011 i have 0 alerts about DNS.
Streange is that my IP adres change to 192.168.1.101 (from 31.03.2011) and 192.168.1.103 (from 10.04.2011). Only today i have this streange DNS alert !!
Nothing about svhost.exe and dns alerts in my log from 10 last days …
I ask the question because some malwares change your DNS servers in your PC (which is prevalent on router for DNS). So, just to be sure you can check in the properties of Internet Protocol (TCP/IP) that Obtain DNS server address automatically is still checked.
Try to read once again what EricJH wrote. We know well what for second DNS is, and what is going on when first fail. Also - i know why i see 2 DNS in my Network Security Policy - bicouse i put them there and make an exeption for them.
What you looking for - is not all - and it’s not a point of this post … i think you have bug in your software - that’s why comodo (again) show me alert (on same machine) that first and second DNS (udp) try to comunicate with same IP that is in Exeption List and marked green.
My IP adress change 3 times - only one time firewall show me (same udp) DNS alert.
Maybe we don’t understand eachother - I have already steup rule in my Network Security Policy…