iptables freezes mozilla

[panos]

I am working on building a basic iptables firewall using a script. I have dropped everything on the INPUT chain and opened only a hole for people to access my web server at port 80 and for me to accept replies from web sites I requested web pages from. I do not restrict the OUTPUT chain yet (the default state is ACCEPT) or the FORWARD. I have both Konqueror and Mozilla on my system (RedHat EL). I also allow UDP packets through the INPUT chain. Now, when I start Mozilla it loads just fine, but when I try to type a new URL it freezes (Only when I press a character while I am in the URL address text box). That would not be strange if Konqueror was behaving the same, but it does not. I can load konqueror and serf the web just fine. Anybody knows what's up with that. Sorry for the long message, I was just trying to describe the problem in detail

[starfish]

At first I thought it may have been DNS, but allowing inbound/outbound UDP should fix that problem. If your machine is a DNS server, you hould also allow TCP port 53 inbound as well.

Do you allow full inbound/outbound access on TCP/UDP to localhost (127.0.0.1)? Many applications require this open to work. Mozilla may be one of them.

At the end of your INPUT, OUTPUT and FORWARD chains you should add a LOG and DROP jumps as seen below.

http://www.linuxhomenetworking.com/l...m#_Toc88490120

You should then check your /var/log/messages file to see what is being blocked and then add entries to the chains to facilitate this activity.

Hope this helps.

[panos]

It seems that Mozilla needs TCP/UDP on localhost to operate correctly. It was kind of silly of me to forget the localhost, but thank you for your post, you were right on the money.