Is the following configuration correct to allow IPP printing to a remote public printer (to any IP address)?
iptables -A IN -i eth1 -p tcp -m tcp --sport 631 -m state --state ESTABLISHED -j ACCEPT
iptables -A OUT -o eth1 -p tcp -m tcp --dport 631 -j ACCEPT
Should I accept RELATED incoming requests too?
Is it normal that the external printer sends unrelated requests (from source port 631) back to my computer? Is it safe to block those requests?
Note that printing seems to work correctly with those settings, but I wonder if blocking those unrelated requests may impact error reporting/recovery.
