Mysterious reboot

Mike Loiterman mike at
Thu Feb 16 12:32:35 PST 2006

Wouter Spierenburg <mailto:wouter at> wrote:
> Try adding the following to /etc/sysctl.conf:
> kern.maxfiles=65535
> kern.maxfilesperproc=20000
> net.inet.tcp.delayed_ack=0
> net.inet.ip.maxfragpackets=10
> kern.ipc.somaxconn=2048
> then 'cd' to /usr/src/sys/i386/conf
> and add the following lines at the bottom of the file:
> options         TCPDEBUG
> options         RANDOM_IP_ID
> options         TCP_DROP_SYNFIN
> options         NMBCLUSTERS=65535
> options         NMBUFS=40960
> save the file, and follow these steps:
> /usr/sbin/config -g SERVER
> cd ../../compile/SERVER
> make depend
> make
> make install
> #if all went well:
> reboot
> The system will then come back up with tuned parameters, allowing more
> in/outbound connections and better packethandling.

Before I make these changes, I would like to just get a second opinion from
the list about their value and what impact, if any, they might have on
system stability, compatibility, etc.

Wouter, please do not take offense to this!  I sincerely appreciate your
advice, but this is a production system, so I'm careful about what changes I
make when I don't explicitly understand what is going on.  I'm not familure
with a few of those options.  

I also noticed that that you used the old (traditional) way of recompiling
the kernel.  Is that necessary or can I use the newer `make buildkernel
KERNCONF=x && make installkernel KERNCONF=x'.  I'm simply more comfortable
with that way...

Thanks to all

Mike Loiterman
Tel: 630-302-4944
Fax: 773-442-0992
Email: mike at
PGP Key: 0xD1B9D18E

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