How to figure out software or hardware RAID?

[sup3rcarrx8]

Hi guys,

One of the servers in our office went down and the person that set this machine up is long gone. We're in need of finding out of it's a software or hardware RAID. We're thinking it's a CentOS raid setup but not sure how to repair the other hard drive (assuming it's a failed drive in the RAID 1 system). Can anyone help out on the following error messages we see when CentOS is booting up? I see errors related to sda2, logical i/o buffer errors etc.

The motherboard is also a Intel board but can't figure out where the model # is located in the BIOS or the physical board itself. The system has 2 WD Green 3TB drives in the RAID setup.

 

[Robert17]

I located a forum post that may offer some insight. Scroll a few posts down, around #5 or so.

 

[sup3rcarrx8]

Any idea how to run that command if I only have grub access? I can't run other commands to verify which drive is actually the failed drive in the RAID1 such as cat /proc/mdstat

 

[HankB]

I can think of a couple strategies.
1) boot a live (Linux) CD/USB
2) Unplug drives one at a time and try to boot.

Most likely it is S/W RAID. That's the recommended setup for Linux. If it is two drives that are mirrored and with grub installed to both, if the first drive goes bad the system will likely not boot. The BIOS is most likely not smart enough to try to boot from the second drive if the first goes bad. If the bad drive is removed the system may boot from the other drive.

Good luck!

 

[sup3rcarrx8]

I can think of a couple strategies.
1) boot a live (Linux) CD/USB
2) Unplug drives one at a time and try to boot.

Most likely it is S/W RAID. That's the recommended setup for Linux. If it is two drives that are mirrored and with grub installed to both, if the first drive goes bad the system will likely not boot. The BIOS is most likely not smart enough to try to boot from the second drive if the first goes bad. If the bad drive is removed the system may boot from the other drive.

Good luck!

We were able to do option 2 and my coworker was able to mount it when we plugged it into another CentOS machine. We plan to transfer the data to a external drive and re-do the server setup to something easier to maintain. Rather than having the OS and data on the same RAID 1 partition, would you guys recommend installing Ubuntu/CentOS onto a SSD for the OS and have the data pointed to a RAID 1 array? Currently the OS/data are on the same RAID 1 partition. This is for a SFTP server by the way.

We'll also be planning to use the built in RAID controller of a Dell server we have laying around. Will there be any significant cons/pros of having using the hardware RAID on this motherboard vs. a software RAID as it is now?

 

[HankB]

We were able to do option 2 and my coworker was able to mount it when we plugged it into another CentOS machine. We plan to transfer the data to a external drive and re-do the server setup to something easier to maintain. Rather than having the OS and data on the same RAID 1 partition, would you guys recommend installing Ubuntu/CentOS onto a SSD for the OS and have the data pointed to a RAID 1 array? Currently the OS/data are on the same RAID 1 partition. This is for a SFTP server by the way.

I would never put the OS and data in the same partition. I have two file servers running Debian server and with 2x 3TB drives each for data storage. One only has two SATA ports so I partition the drives as two mirrored (RAID1) partitions. A small partition (about 10GB) holds OS. The other holds data. The other system has 4 SATA ports so I used an old laptop drive for boot/OS and the large drives are entirely data. It's a little easier to configure that way. You could use an SSD drive for OS but would see little benefit from it. Better to swap it into a laptop and use the laptop drive in the server.

We'll also be planning to use the built in RAID controller of a Dell server we have laying around. Will there be any significant cons/pros of having using the hardware RAID on this motherboard vs. a software RAID as it is now?

I use S/W RAID. I can pull drives and put them in any other PC and activate the RAID. With H/W RAID you probably need to put it in a system with a matching RAID controller. Also with S/W RAID I can partition a drive and RAID the partitions. With H/W RAID I think it manages the entire drive.

Good to hear you are making progress.