Troubleshooting a Freeze

[Ryan Sandridge]

Are there any general or specific tips on how to figure out what is  
causing FreeBSD to just freeze up?  The machine is not at my physical  
location, and I log in using ssh.  I've checked all the logs in  
/var/log for some kind of clue, but I haven't found anything helpful.   
The machine has worked fine for over 6 months, until the last few days  
it freezes up at apparently random times, normally within the first 12  
hours of being up.  While many ports have been added over the past 6  
months, nothing was added on or around the time I started experiencing  
the problem.

I guess I was wondering what some first steps people would take to  
troubleshoot an unexplained system hang.


Some details:

FreeBSD 4.8-RELEASE #0: Thu Apr  3 10:53:38 GMT 2003
     root at freebsd-stable.sentex.ca:/usr/obj/usr/src/sys/GENERIC
Timecounter "i8254"  frequency 1193182 Hz
CPU: AMD Athlon(tm) XP 1800+ (1541.22-MHz 686-class CPU)
   Origin = "AuthenticAMD"  Id = 0x662  Stepping = 2
    
Features=0x383fbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE, 
MCA,CMOV,PAT,PSE36,MMX,FXSR,SSE>
   AMD Features=0xc0480000<MP,AMIE,DSP,3DNow!>
real memory  = 536805376 (524224K bytes)
avail memory = 517066752 (504948K bytes)

open ports: ssh, smtp, imaps, pop3s, 8080 (http), https

Thanks,
   Ryan