8.0 network problem

[David Warren]

Hi all,

     I've got a persistent problem with my LAN.  I'm running a FreeBSD 8.0
box as a home server performing the following functions for wired and
wireless networks: router; firewall; DHCP server; and file server.  For what
it's worth, I've got ZFS up and running as the main filesystem.  The
recurring issue is that file transfers from the FreeBSD box to computers on
the wired network (gigabit) start out fast and then become agonizingly
slow.  I'm sharing home directories over Samba, and those transfers work
briefly and then tail off to a few kilobytes per second.  The failure is
somewhat predicatable in that it tends to happen once a few hundred
megabytes have been transferred.  I've swapped out hardware, I've Googled
extensively, and all of the (possibly benign) error messages that I've found
have been eliminated.  I'm happy to post logs, configs, etc., and I'd
appreciate any help with a diagnosis.  For the moment:

> uname -a
FreeBSD EightOh.dew.home 8.0-RELEASE-p2 FreeBSD 8.0-RELEASE-p2 #0: Tue Jan
5 21:11:58 UTC 2010
root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC
amd64

> ifconfig

em0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=9b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,VLAN_HWCSUM>
        ether 00:0e:0c:b7:71:44
        inet 192.168.0.1 netmask 0xffffff00 broadcast 192.168.0.255
        media: Ethernet autoselect (1000baseT <full-duplex>)
        status: active
ral0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 2290
        ether 00:1f:1f:3f:76:f3
        media: IEEE 802.11 Wireless Ethernet autoselect mode 11g <hostap>
        status: running
nfe0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        options=8<VLAN_MTU>
        ether 00:01:29:d4:2d:6b
        inet XXX.XXX.XXX.XXX netmask 0xfffffc00 broadcast 255.255.255.255
        media: Ethernet autoselect (100baseTX <full-duplex,flag0,flag1>)
        status: active
plip0: flags=8810<POINTOPOINT,SIMPLEX,MULTICAST> metric 0 mtu 1500
lo0: flags=8049<UP,LOOPBACK,RUNNING,MULTICAST> metric 0 mtu 16384
        options=3<RXCSUM,TXCSUM>
        inet6 fe80::1%lo0 prefixlen 64 scopeid 0x5
        inet6 ::1 prefixlen 128
        inet 127.0.0.1 netmask 0xff000000
wlan0: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> metric 0 mtu 1500
        ether 00:1f:1f:3f:76:f3
        inet 192.168.1.1 netmask 0xffffff00 broadcast 192.168.1.255
        media: IEEE 802.11 Wireless Ethernet autoselect mode 11g <hostap>
        status: running
        ssid FreeBSD_AP channel 7 (2442 Mhz 11g) bssid 00:1f:1f:3f:76:f3
        country US authmode WPA privacy MIXED deftxkey 2 TKIP 2:128-bit
        txpower 0 scanvalid 60 protmode CTS dtimperiod 1 -dfs
pflog0: flags=141<UP,RUNNING,PROMISC> metric 0 mtu 33152

Thanks in advance!

Dave