Snort network instruction Mac OS X

Question

I'm trying to learn network intrusion detection. When I try to launch Snort, in IDS mode, I get this message (I'm running Mac OS X):

Initializing Network Interface en1
ERROR: OpenPcap() FSM compilation failed: 
    syntax error
PCAP command: snort
Fatal Error, Quitting..

How can I fix this problem?

Answer 1

A few things to try:

1. Make sure you are running Snort as root (or a user with permissions to drop into promiscuous mode.)

2. Make sure your configuration is valid. (snort -t -c snort.conf I believe.)

3. If all else fails ask on the forums at snort.org. They're helpful.