Server RAID5 options (1 Viewer)

[eetaylog]

I currently run a server that has 4*500Gb HDD's in a RAID0 configuration. Whilst ive been happy with this up until now, im a bit nervous that one of the disks is going to fail on me which would mean ill lose all my data, so id like to switch to a RAID5 array.

My current server uses something very similar to this PCI RAID controller to handle the array, but im wondering whether to simply upgrade to a motherboard that has built in RAID capabilities.

so the question is, are there any dis/advantages to choosing either method??

 

[rtv]

At present I'd call RAID5 a poor-man's solution. Considering the cheap prices for terabyte harddisks there's almost no reason to choose the drawbacks of RAID 5 over RAID1:
- much lower write performance
- much pricier controllers (if they are supposed to work well - e.g. better than software RAID)
- no simple disaster recovery (with RAID 1 you could simply use the remaining drive)

 

[deebo]

Solaris Operating System - ZFS Learning Center

 

[eetaylog]

At present I'd call RAID5 a poor-man's solution. Considering the cheap prices for terabyte harddisks there's almost no reason to choose the drawbacks of RAID 5 over RAID1:
- much lower write performance
- much pricier controllers (if they are supposed to work well - e.g. better than software RAID)
- no simple disaster recovery (with RAID 1 you could simply use the remaining drive)

thanks for the info, so can you recommend a pci controller that would do a good job of handling RAID1? ive seen some silicon 3114 chip software controllers on ebay, but dont know whether theyll last...here or here

 

[disaster123]

If you want a really fast AND HARDWARE based Raid 1 buy a 3ware 9650SE-2. The Cheap chipset based raids are only Softwareraids / the driver handles all the load.

 

[eetaylog]

i want to stick to software RAID ideally because:

1) i dont want too spend too much on a RAID solution
2) by using software RAID i can transfer the RAID array over to another pc if i want to
3) if a software controller dies i can just buy another card with the same driver chip to replace it and carry on as normal.

 

[disaster123]

> 1) i dont want too spend too much on a RAID solution
OK - so if you only need a cheap PCI Card buy a one from promise.

> 2) by using software RAID i can transfer the RAID array over to another pc if i want to
You can do the same with a 3Ware Controller.

> 3) if a software controller dies i can just buy another card with the same driver chip to replace it and carry on as normal.
You can do the same with a 3Ware Controller

 

[eetaylog]

> 1) i dont want too spend too much on a RAID solution
OK - so if you only need a cheap PCI Card buy a one from promise.

> 2) by using software RAID i can transfer the RAID array over to another pc if i want to
You can do the same with a 3Ware Controller.

> 3) if a software controller dies i can just buy another card with the same driver chip to replace it and carry on as normal.
You can do the same with a 3Ware Controller

lol, i didnt know that about 2) and 3), i thought it only applied to software based controllers. it still leaves me with the problem of not having much of a budget to rebuild my RAID setup though, so ill stick to software. what is 'promise' by the way?

 

[disaster123]

I don't know if 2 and 3 works for every controller but it works for adaptec and 3ware.
Promise is a company building cheap Raid PCI cards software based - but as i've seen they are no longer cheap... so forget about it.

 

[rtv]

Btw: "real" Software RAID (done by the OS) outperforms those Promise/Chipset solutions in most scenarios and CPU load for RAID 1 would hardly be noticeable.

Only drawback of software RAID with windows versus linux is that you can't do it for the system partition itself.

Maybe a cheap external drive housing which comes with a RAID controller (not a full NAS) would be a solution as well if you plan to use it for media storage?