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User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.3.1) Gecko/20030510

Description of problem:
ifup-post contains code to open the firewall for DNS replies when PEERDNS=yes.

However, there is a grep to prevent the repeated addition of DNS rules, as in:

    if ! iptables -L RH-Lokkit-0-50-INPUT -n | grep -q $nameserver ; then

This of course matches any rule which the nameserver IP address is entered for.
Hence if your DNS server (or relay) has other services (smtp, etc) which the
firewall is explicitly open for, then the nameserver entries are not added and
DNS fails to work.

I have changed mine to:

    if ! iptables -L RH-Lokkit-0-50-INPUT -n | grep -q "$nameserver.* --sport 53
" ; then

This slightly more specific grep ensures that only DNS lines are considered.

Version-Release number of selected component (if applicable):
initscripts-7.14-1

How reproducible:
Always