[K12OSN] K12LTSP 6 server requirement

[James P. Kinney III]

On Sat, 2007-06-09 at 17:41 -0400, Rob Owens wrote:
> On Sat, Jun 09, 2007 at 09:19:19AM -0400, James P. Kinney III wrote:
> > Athlon 64 x2 4600+, 4GB RAM, dual 300GB SATA 300 drives RAID 1 (software
> > RAID: each drive has the following partitions: 100MB, 1GB, 40GB, 60GB,
> > rest. the 100MB pairs make up the /boot, the 1GB is NOT raid and makes
> > the swap, 40GB pair makes /, 60GB pair makes /var. and the rest is
> > for /home)
> 
> I'm always struggling w/ choosing my partition sizes.  Why did you
> choose such a large / and /var partition?

Because:

1. 40GB for / give me oodles of room for adding tons of stuff later in
places like /opt and /usr/local.

2.a. 60GB for /var is great for keeping around all the yum downloaded
files for later reuse. Plus I don't have to worry about /var ever
filling up and locking the system up hard (if /var fills the mandatory
lock files can't be written and BAD THINGS (tm) happen). Also since /var
is where all the log files get locally written I have the space to turn
up the logging level when ever I need to debug something and need more
details.

2.b. /var is also where database data and web files are now stored in
RedHat variant systems. Now I think that's not the correct place
(/usr/local/data make MUCH more sense but I'm not on the Linux
Filesystem Standards Board) but it's easier to accommodate than ignore.

3. I have the space! Hard drives are dirt cheap compared to my time to
add a new one and migrate data and modify /etc/fstab and remount new
drives, etc. Moving around something like / or /var is not something I
can do remotely (at least easily) as both of those partitions require
runlevel 1 (so no networking or any service running). I _can_ do it
remotely with a remote console (KVPIP or console over serial port with a
modem) but it is easier and often less expensive to make sure I have
ample space on those two critical partitions to begin with.


Now a better question is: 

Why have /var in a separate partition to begin with? 

Answer: Because _IF_ a process blows up and spews log file data from
hell (I've seen this happen) and /var is on the same partition as /,
when  / fills up the system hard locks and dies and can't be reopened
even in runlevel 1 (even root must be able to write to the drive just a
single byte in RL 1). To recover from this requires putting the drive
into another system and cleaning up the mess enough for a bit of free
space. Then putting the drive back in the original box and cleaning up
the mess completely. While this is doable it is not pleasant when tech
support is a long way away (air flight distance) and the local "hands
on" support is not comfortable doing surgery on a server with phone
conferencing for instructions. I have seen many situations where /var
always was granted it's own _entire_drive_ (BIG systems with many
hundreds of users). 
> 
> -Rob
> 
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-- 
James P. Kinney III          
CEO & Director of Engineering 
Local Net Solutions,LLC        
770-493-8244                    
http://www.localnetsolutions.com

GPG ID: 829C6CA7 James P. Kinney III (M.S. Physics)
<jkinney at localnetsolutions.com>
Fingerprint = 3C9E 6366 54FC A3FE BA4D 0659 6190 ADC3 829C 6CA7
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