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Installation with SSD and RAID combination

Offline Chris

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Installation with SSD and RAID combination
« on: September 05, 2014, 12:00:16 PM »
Hello,

so I have the following setup available:

2 GByte RAM
1.6 GHz Quadcore
250 GByte SSD on PCIe
4 x 4TByte on SATA

...and now I would like to make the best of it.

It's Server only, private environment for two persons. Usecases are IMAP email (various identities and Domains), shared storage for photos and music, a little bit of PHP/MySQL development platform

I don't really worry too much about the operating system. If it is gone, it's gone - no big deal. But my photos and emails are important, I want to make sure they survive even if one hard drive fails.

So what I thought would make best use of the setup:
Swap, boot sequence, and operating system on the SSD,
photos and emails and all the other ibays on a RAID 5 for the 4 SATA HDDs.

I have seen the installation offers an extended graphical CentOS installation tool where I can set up the RAID.

But knowing the basics does not replace experience.
How would you partition the HDDs, especially the SSD? And which mounting points would you place where?

Thank you for your help!

Offline Stefano

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Re: Installation with SSD and RAID combination
« Reply #1 on: September 05, 2014, 12:08:11 PM »
welcome here

my 2c: forget about ssd, use only sata disks, raid5 (1 spare)

when you're done, think about backup

Offline Chris

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Re: Installation with SSD and RAID combination
« Reply #2 on: September 05, 2014, 12:44:08 PM »
Thank you for the welcome :)

Really? I feel kinda bad for ignoring the SSD. I mean... I have it... it's fast... reliable... would be a shame if it would only catch dust

Offline Stefano

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Re: Installation with SSD and RAID combination
« Reply #3 on: September 05, 2014, 12:47:15 PM »
You need a heavily customized setup to use all your disks.. i.e. install O.S. on ssd (with no raid option), then manually setup your raid array, mount it and so on..

IMVHO you should just install with raid5 option on your sata disks.. and you are done

Offline Chris

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Re: Installation with SSD and RAID combination
« Reply #4 on: September 05, 2014, 12:58:05 PM »
Oh, setting up the RAID after the installation is in the range of things I am capable of.

However changing OS' configuration in a way that ensures that the ibays, MySQL-data, httpd and especially the mails will be stored on the RAID and no longer on the "formerly standalone" SSD... that is more difficult. Especially since I don't know which keywords to use in a search when looking for a good description on how to do it.

Would you have a hint on where to look for a "howto" on this specific topic?
Then I could read through it and decide if this is in the area of things I can do.

Offline Stefano

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Re: Installation with SSD and RAID combination
« Reply #5 on: September 05, 2014, 01:04:12 PM »
http://wiki.contribs.org/AddExtraHardDisk

please be aware that mysql db will stay on ssd..
I repeat, IMO you are looking for troubles :-)

Offline Chris

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Re: Installation with SSD and RAID combination
« Reply #6 on: September 05, 2014, 02:37:41 PM »
Understood. For changing the mysql-data storage I'd have to change the datadir in /etc/mysql/my.cfg

Yes... I know it is most likely that I am indeed looking for trouble. But then again... from my experience the greater pain in the ass is migrating the data after a few years from one server system to the next. So I'd rather have them away from the OS :)

I guess the usecase for a small "family-homeserver" is a bit different from a full blown company server, where availability is essential.

Offline Stefano

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Re: Installation with SSD and RAID combination
« Reply #7 on: September 05, 2014, 02:50:24 PM »
Understood. For changing the mysql-data storage I'd have to change the datadir in /etc/mysql/my.cfg

you can do it via a custom template (see wiki for info)

Quote
Yes... I know it is most likely that I am indeed looking for trouble. But then again... from my experience the greater pain in the ass is migrating the data after a few years from one server system to the next. So I'd rather have them away from the OS :)

SME is linux.. if you use its backup feature you can move to another server without problems
if you wish to move to another server o.s. you need to do what to do

using a single disk for o.s. can be done, but you need to (heavily) modify standard behaviour if you wish to keep o.s. separate from data

in any case, following the wiki page I told you and using lvm volumes you can create many mount points (/home /opt /var) and achieve what you are looking for..

it could be a good exercise but, let me say, it's not worth the resut and you will be on your own if you choose so.

Quote
I guess the usecase for a small "family-homeserver" is a bit different from a full blown company server, where availability is essential.

I guess the usecase for a small "family-homeserver" should be hassle free.. just install, configure and forgot it
moreover, storing a big amount of data on (any kind of ) a server is a bit dangerous without a backup.. this is true regardless of the use of the server itself IMHO