Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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I recently installed dnsmasq on my linux box. Everything seems to be working ok locally--I changed the resolv.conf to show that the loopback address is the nameserver and when I do an nslookup (locally) I get a very quick reply:
UPDATE: I removed dnsmasq and installed BIND instead, just to see if it is an issue with DNSMasq. BIND has the same issue. Local requests (via my terminal window) work fine. Requests from other PCs do not.
So now I am figuring that it is a firewall issue. I've opened port 53 in both directions (from fw to net and from net to fw). Are there other ports which need to be opened?
Does port 53 need to be open to both UDP and TCP requests?
I have been reading a bit more about how DNS works and one site mentioned that the initial request comes in via UDP on port 53 (and then reverts to TCP if the reply is too large for a UDP packet). Is this the case and if so do I need to open port 53 for UDP requests in Shorewall? (Right now it is only configured to allow TCP requests.)