Recommend me OS based or Onboard RAID.

[jai_123]

I am planning to setup a server with Supermicro X11SSL-F with 2 SSD (Intel S3510) on RAID 1. My objective is to create VM (KVM based) out of the node (node OS: CentOS 6.7 preferred). The motherboard support RAID 0, 1 and 10 via C232 controller.

OS Compatibility Chart: http://www.supermicro.com/support/resources/OS/C232.cfm

Which type of RAID will be recommended, fully OS controlled?
I heard the onboard Intel C232 is good choice, where as suggestions OS controlled will help in easy drives migrated to another computer if needed.

Please help me with your valuable suggestions.

 

[drtweak]

Onboard RAID is better to deal with. You set it up, OS see's it as one drive. You should be able to move those drives to any compatible motherboard so long as they use the same SATA/RAID drivers.

With OS RAID you install the OS on one drive, convert it to a dynamic drive, then add the second drive, convert that to a dynamic drive, then make a RAID 1. Doing RAID 1/0 on software isn't as huge of a deal as their is little overhead. either way both version of RAID would be mainly CPU driven. if you wanted a RAID 5/6 definatly get a RAID card.

I'm more of a hardware RAID person, only thing is if BIOS gets reset or upgraded more than likely the RAID settings get wiped and lot of people have issues getting them back.

 

[samopa]

IMHO, for your data, do not use ON-BOARD RAID Solution, because if by one chance your on-board RAID malfunction, you have to replace your entire motherboard (same mobo) to save your data, provided that the motherboard replacement is still available (not discontinued product).
When your motherboard replacement is not available then your data is toast.

For your data, IMHO, it is safer to use Software (OS) RAID, so if there are hardware controller malfunction, you can move them to another mobo (any mobo) and it still works.
Better solution is to use an add-in RAID Card, so in the event there are HW malfunction, you can just replace the add-in card, and your data is still safe. You get the best of both worlds.

 

[jai_123]

Thank you very much for your suggestions. As suggested in case of on-board RAID malfunction, it may be difficult to get same motherboard replacement, as most of the manufacturers discontinue the motherboard after a year or two.

I think the OS RAID 1 will be best for me considering the possibility to move HDD to another server (any motherboard) in case of failures. And no risk of BIOS gets reset or upgraded and RAID settings are lost.

I am wondering is there a chance the add-in RAID card can malfunction. Could there be similar risk if new similar RAID card is not available ? Just for understanding in case of RAID card failure we need new card with similar hardware controller to retrieve data?

 

[drtweak]

If you get a good brand like LSI, most of their cards can see RAID's from other cards and import them. Sometimes it may not (I moved from a Dell SAS 5 HBA (pretty much a LSI SAS 1068) that does RAID 1 and 0) to a LSI MEGARAID 8888LMP and it could see I had a RAID but it could not import it. If i had moved that to another Dell SAS 5/6 or Dell PERC 5/6 it could pick it up, import it, and i would keep chugging along. So some cases no, but some cases yes. More so as long as you stay within the same brand yes.

Just one thing, it doesn't matter what you do HAVE A REGULAR BACKUP!

 

[samopa]

Thank you very much for your suggestions. As suggested in case of on-board RAID malfunction, it may be difficult to get same motherboard replacement, as most of the manufacturers discontinue the motherboard after a year or two.

I think the OS RAID 1 will be best for me considering the possibility to move HDD to another server (any motherboard) in case of failures. And no risk of BIOS gets reset or upgraded and RAID settings are lost.

I am wondering is there a chance the add-in RAID card can malfunction. Could there be similar risk if new similar RAID card is not available ? Just for understanding in case of RAID card failure we need new card with similar hardware controller to retrieve data?

Just as drtweak said, it depends, sometimes it works some other times not. Many factor can affect it, firmware, manufacturer, chipset used, drivers, revisions, etc.

But if you only need RAID 1 capability, you can buy few cheap add in card (two or three), used one and keep others for spare, any times the one used goes kaput, you can always replace it with your spare and save/move your data. Because RAID 1 does not need fancy computational resources (it just copy any write on one disk to the other), buying expensive add in card can be overkill. IMHO $25-$40 card is sufficient for RAID 1 setup, and you can pile up some card for spare (make sure its same brand, type, and revisions). I had used some which has Marvell 88SE9230 in them, and they does what they meant for, and as bonus Marvell Card usually come with nice and tidy utility.