Take the 2-minute tour ×
Server Fault is a question and answer site for professional system and network administrators. It's 100% free, no registration required.

If OUTPUT chain default policy is ACCEPT, is there any use case for the following rule?

-A OUTPUT -o $INTIF -s $EXTIP -d $INTNET -j ACCEPT
share|improve this question

1 Answer 1

Some simple tools use this as a way to count traffic matching a particular rule. There can be other rules later which would block packets if they are not explicitly allowed earlier.

share|improve this answer
    
Still I don't understand in which cases I may have a packet, coming out of LAN, which has src ip of WAN and directed to LAN devices. –  Michael Mar 13 '11 at 13:20
    
@Michael: There may be a NAT rule for LAN based packets sent to the external IP (web, mail server, etc.). This would count those packets. –  BillThor Mar 13 '11 at 13:54

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.