Main Area and Open Discussion > Living Room
Building a home server. Please help, DC!
JavaJones:
Properly implemented, RAID reduces your risk of downtime. It does nothing to improve your reliability from an engineering perspective.
-40hz (August 02, 2011, 03:27 PM)
--- End quote ---
That is the most concisely stated view of RAID I've seen yet. Well said!
Regarding a presentation/article trying to clear up the RAID question, I think it's clearer than ever now that SSDs are widespread and relatively affordable:
For virtually all "home" users, including enthusiasts and gamers, RAID is unnecessary and, if anything, a potential liability. Don't use it. If you want speed, get an SSD. If you want redundancy, do regular backup. End of story. Those at an enterprise level who need RAID will know and don't need further explanation. That's my view anyway.
- Oshyan
40hz:
If you want speed, get an SSD. If you want redundancy, do regular backup. End of story.
-JavaJones (August 03, 2011, 02:19 PM)
--- End quote ---
Bingo! :Thmbsup:
f0dder:
If you want speed, get an SSD. If you want redundancy, do regular backup.-JavaJones (August 03, 2011, 02:19 PM)
--- End quote ---
...and possibly couple it with RAID Mirroring. That does add real redundancy and isn't (just) for downtime reduction :)
40hz:
If you want speed, get an SSD. If you want redundancy, do regular backup.-JavaJones (August 03, 2011, 02:19 PM)
--- End quote ---
...and possibly couple it with RAID Mirroring. That does add real redundancy and isn't (just) for downtime reduction :)
-f0dder (August 04, 2011, 02:01 PM)
--- End quote ---
True. :)
Unless you have a controller issue which screws up both drives. :o
Weirdest thing about RAID-1. When it breaks, it sometimes takes out both drives.
I had this happen to clients twice in my career. So it can't be that rare an occurrence in the field. Which is why I'll only use RAID-1 for mirroring the OS drive thereby reducing it to a 'downtime reduction only' function.
Because I can always reinstall a disk image or (if it comes down to brass tacks) do a scratch reload of the OS (*choke*) without losing anything critical belonging to the client.
---
Never tried RAID with SSD. (Not being wealthy has its downsides. ;D) Is anybody doing that? And if so, does it adversely affect the life of the SSD drives? Mirroring probably wouldn't. But RAID-5 should since there's so much extra R/W activity generated by all the striping plus parity info being written to the drives. (Note: Save a dinky 1 meg file to a server with RAID-5 and watch das blinkin' lights come alive with motion and color. Freekin' dance of fireflies is what it is! Save anything to a RAID-5 array and it goes nuts "gettin' busy.") That can't be good for an SSD drive over the long term.
Anybody know anything about this? :huh:
f0dder:
Weirdest thing about RAID-1. When it breaks, it sometimes takes out both drives. -40hz (August 04, 2011, 02:58 PM)
--- End quote ---
Shit happens :) - drives from the same batch can die shortly within eachother (especially if you have very disk-intensive rebuilds... mirroring isn't too bad, raid-5 is BAD). And then there's stuff like power surges etc. So yeah, stuff dies.
I had this happen to clients twice in my career. So it can't be that rare an occurrence in the field. Which is why I'll only use RAID-1 for mirroring the OS drive thereby reducing it to a 'downtime reduction only' function.-40hz (August 04, 2011, 02:58 PM)
--- End quote ---
Backups tend to run nightly - so mirroring can potentially save you several hours worth of lost data. And of course reduced downtime is a nice bonus, that does require hotswap capability though :)
Never tried RAID with SSD. (Not being wealthy has its downsides. ;D) Is anybody doing that? And if so, does it adversely affect the life of the SSD drives? Mirroring probably wouldn't. But RAID-5 should since there's so much extra R/W activity generated by all the striping plus parity info being written to the drives.-40hz (August 04, 2011, 02:58 PM)
--- End quote ---
Raid-5 (and other "big storage" schemes) would be silly on SSD until their storage capability goes massively up. The added writes of raid-5 is a real concern, but apparently the current crop of SSDs die off by crap electronics well before the erase cycle limit is reached :o :o :o
The drives are mainly useful for cache layers or or really I/O intensive stuff like databases. Mirroring might make sense, striping could (but you'll need expensive motherboard and I/O cards, SATA and PCI-e bandwidth considered?).
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version