[wplug] Re: MD on atop of LVM (or LVM2's native RAID), instead of LVM on top of MD -- WAS: Install Question

[Drew from Zhrodague]

> What happens when /var corrupts, eats up all your disk space, etc???

 	Same thing that happens when the power supply fails, SAN goes 
down, or the core switch gives birth to Cthulu: box goes down.

 	This is why we have redundant servers, and our common protocols 
support multiple hosts (DNS, SMTP, etc), plus things like load-sharing.


> 2GB?  2GB?  For /var?  Where you been?  ;)

 	Many many many many places durring my career. My resume reads like 
a list of dotcom losers!

 	If you log into a FedEx Ground server, and do a df, it produces a 
partition list that scrolls off the screen. For a minute or two. All 2G 
partitions. That is what happens when mainframe people administer UNIX.


> Make a stock 4-8GB /var.

 	*Poof!* too small for a public webserver.


> Beyond that, further segment /var further into /var/www for web servers
> (ideal from a security standpoint), /var/ftp for FTP servers (again,
> security enhancing), /var/mail for mail servers, /var/spool, /var/lib/*,
> etc... as appropriate.

 	Wow, how bizarre. How is having a seperate partition for your 
htdocs good for security?


> I never see people end chuckling when they see Linux sysadmins who start
> touching enterprise HP/UX, Solaris and other platforms and go, "What is
> this 'partition table'?  Why aren't you using all space?  Etc..."

 	I haven't seen any Suns in production in a while. I remember their 
install instructions had some sort of formula for determining the proper 
size of the swap partition (which was actually /tmp). Otherwise, their 
disk partitioning scheme is cartoon-rediculous. Slapstick wacky Sun 
disklabel. I've seen lots of suns have disks hanging off the thing like an 
old Mac kept alive by 8 or 9 50M disks, presumably because they ran out of 
space on their various partitions.

 	You gotta remember that a good UNIX machine will live out it's 
life, and be repurposed several times after that. Sometimes it requires 
more software, more data, or more users. If you condemn yourself to 
running out of space, I guess it is your replacement that will have to 
deal with it! Then again, disks are cheap, and large. A / partition makes 
things easy for me to set it up, and not have to think about it again.

 	Of course, now we actually have SANs...

-- 

Drew from Zhrodague		http://www.WiFiMaps.com
drew at zhrodague.net		http://www.pghwireless.net
 				http://www.zhrodague.net/~drew