Not seeing data on an unnumbered interface...

[Kurt Buff]

All,

I'm having a very strange problem. I'm running ntop - the unnumbered
interface is not receiving any data.

Running 'tcpdump -i em0' also gets no data. I am really baffled - I've
tried it against a switch that I know has a correctly configured
mirror port, as I have ntop running on another machine and that works
fine in the same port, but it's running 7.1-RELEASE.

Anyone have thoughts on this?


# uname -a
FreeBSD zntop.mycompany.com 8.0-RELEASE FreeBSD 8.0-RELEASE #0: Sat
Nov 21 15:48:17 UTC 2009
root at almeida.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

# cat /etc/rc.conf
hostname="zntop.mycompany.com"
ifconfig_rl0="DHCP"
ntpdate_enable="YES"
ntpdate_flags="-b 192.168.10.191"
sshd_enable="YES"
ntop_enable="YES"
ntop_flags="-d -u ntop -P /home/ntop/databases -K -L -t 6 -o -i em0 -W 0"

zntop# ifconfig
em0: flags=8902<BROADCAST,PROMISC,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=9b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM>
        ether 00:1b:21:04:2a:c5
        media: Ethernet autoselect (100baseTX <full-duplex>)
        status: active
rl0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=8<VLAN_MTU>
        ether 00:0c:46:b3:43:53
        inet 192.168.24.51 netmask 0xffffff00 broadcast 192.168.24.255
        media: Ethernet autoselect (100baseTX <full-duplex>)
        status: active
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
        options=3<RXCSUM,TXCSUM>
        inet6 fe80::1%lo0 prefixlen 64 scopeid 0x3
        inet6 ::1 prefixlen 128
        inet 127.0.0.1 netmask 0xff000000


Kurt