System locking up.

[Fbsd8]

Graeme Dargie wrote:
> Hi All,
> 
> I have a system that is being problematic, I suspect but I cannot say for sure it is maybe related to ZFS as I have a fairly large ZFS pool on the machine. The system will just lock up, local console does not respond to the keyboard, num lock still changes the led on the keyboard, the system still responds to pings but you cannot ssh to the unit. The behaviour is random the system can be running for 50 days plus with no issues then suddenly it enters this state, the error logs do not show anything.
> 
> System 8.2-RELEASE FreeBSD 8.2-RELEASE #0
> AMD 64
> 
> Running on an AMD x2 5600
> 4gb of DDR2
> Gmirror 80gb boot disks
> 6 x 1.5TB SATA II disks using AHCI
> 
> 
> Loader.conf
> 
> vfs.zfs.prefetch_disable=0
> //vfs.zfs.txg.timeout="5"
> vm.kmem_size="1024M"
> vm.kmem_size_max="1024M"
> vfs.zfs.arc_max="100M"
> vfs.zfs.vdev.cache.size="100M"
> 
> ZFS filesystem version 4
> ZFS storage pool version 15
> 
> Is this likely to be a case of just not enough ram? Or is there some other trouble shooting I could do to try and nail down what is going on as it tends to happen when the ZFS zpool is being accessed heavily.
> 
> Regards
> 
> Graeme
>

My money is on, its a over heating problem or power supply problem.
Open the box to get more air circulating over the motherboard. If the 
problem continues them replace power supply with one that outputs more 
watts. You have a lot of hardware on the current power supply and under 
heavy demand it may not be able to fulfill the power demand the hardware 
requires.