Explicit Congestion Notification was disabled. I put it in the sysctl.conf file anyway, and rebooted. Same problem. :-(
I watched the timing a lot more closely this time, and narrowed the timing to within the start of about a dozen services. One is mDNSResponder. When I ran a restart on this one, everything went crazy. The notes on this one say "This is a daemon which runs on Howl clients to perform Zeroconf service discovery on a network. mDNSResponder must be running on systems that use Howl for service discovery." Using google, it sounds like this is to allow discovery of network services even when there is no DNS server or anything else that would provide this information.
It sure made the firewall howl. I've disabled it and all seems fine now. I have a DHCP server, DNS server, and SAMBA server running on my internal network. mDNSResponder isn't needed here.
Thanks for the help. Without your email, I'd probably not have documented timing/services/etc well enough to spot the problem! :-)
At 08:06 PM 11/28/2004, Wayne Steenburg wrote:
On Sun, 2004-11-28 at 19:06 -0600, Randy wrote:
> I've been noticing something VERY strange with my d-link firewall and
> FC3. Whenever I reboot an FC3 server, about 30 seconds to one minute after
> the server has come to the 'log on' screen, the firewall begins to send out
> massive amounts of broadcasts to my entire home network, bringing
> everything to a standstill. The firewall floods my entire 100Mbps network
> with enough broadcast traffic that almost no packets can get anywhere.
It could be that your router is buggy. Is ecn enabled? From the terminal try:
$ cat /proc/sys/net/ipv4/tcp_ecn
If this returns 1, try turning it off with:
# echo 0 > /proc/sys/net/ipv4/tcp_ecn
I *think* that's only temporary. If that doesn't survive a reboot. edit /etc/sysctl.conf and add the line
net.ipv4.tcp_ecn = 0
# sysctl -p