On Tue, 14 Dec 2010, Jason T. Slack-Moehrle wrote:
Hi All,
I have a new system with 2 Seagate 1TB SATA Enterprise level drives in it.
I want to RAID1 (mirror) these drives. <snip/>
So if I simplify, I must:
Create a software raid partition on each drive
Create a RAID 1 out of that partition and use a mount point of /boot
Create other mount points I might want i.e swap, /home, etc
Create RAID1 out of these partitions
rinse and repeat this for each mount point I want
A few questions:
This system support 16gb of RAM. I have 9gb in it, but I will max it out over the next few months as I find great deals on RAM, what should my SWAP space be? I recall a long while ago that SWAP should match physical RAM.
Any reason I can't just create a single mount point taking up the entire drive and RAID1 the entire thing? Can anyone recommend some ideal mount points and sizes?
What should I account for if my /var/www/html will be very large?
If you have time to experiment a bit, I'd highly suggest encapsulating your RAID design in a kickstart file. You'll need to do some up-front work to get it ready, but once it's done you can re-do your arrangement easily (and repeat as necessary). Here's a sample (that requires two identical drives):
# disk work bootloader --location=mbr clearpart --all --initlabel part raid.01 --size=300 --ondisk=hda --asprimary part raid.02 --size=300 --ondisk=hdb --asprimary part raid.11 --size=1024 --ondisk=hda --asprimary part raid.12 --size=1024 --ondisk=hdb --asprimary part raid.21 --size=20000 --ondisk=hda --asprimary part raid.22 --size=20000 --ondisk=hdb --asprimary part raid.31 --size=1 --ondisk=hda --asprimary --grow part raid.32 --size=1 --ondisk=hdb --asprimary --grow # mirrored mountpoints raid /boot --fstype ext3 --level=RAID1 --device=md0 raid.01 raid.02 raid swap --fstype swap --level=RAID1 --device=md1 raid.11 raid.12 raid / --fstype ext3 --level=RAID1 --device=md2 raid.21 raid.22 raid /srv --fstype ext3 --level=RAID1 --device=md3 raid.31 raid.32
There are many, many ways to alter this setup (e.g., using LVM, using a different set of mount points, not relying on primary partitions).
The reason that /srv gets the lion's share of the disk is that I try to differentiate between files
* created/maintained by running processes (e.g., MySQL) * installed by RPM (e.g., /var/www/error)
both of which belong in /var, and
* data created elsewhere and "fed" to a process (e.g., your video files or HTML pages)
which goes into /srv.