I read that seeing a flag of M in netstat -i is the way to tell which of your interfaces is in promiscuous mode

I run it and I see that eth1 is in promiscuous mode

$ netstat -i
Kernel Interface table
Iface       MTU Met    RX-OK RX-ERR RX-DRP RX-OVR    TX-OK TX-ERR TX-DRP TX-OVR Flg
eth1       1500   0 1770161198      0      0      0 57446481      0      0      0 BMRU
lo        16436   0 97501566      0      0      0 97501566      0      0      0 LRU

This seems to be the case on all the machines I checked (All Centos6.0, both virtual and physical), any idea why ethernet devices would be in such a mode unless someone was running any pcap based app (sudo lsof | grep pcap shows nothing)?

I did not see any mention of promiscuous in any of the config files (sudo grep -r promis /etc)

Any ideas what puts the interface into that mode and why?

p.s. most of the posts I see seem to be security related, this is not that