topic RAID 1 and Linux Disk Partition in Operating System - Linux

RAID 1 and Linux Disk Partition

scott_417 — Mon, 14 Nov 2005 01:42:52 GMT

In a case that DL360 has two mirroring disks, Disk 1 and Disk 2 (RAID 1 implemented). The Operating System is Linux.

If I parse the Disk 1 into:

hda1 for OS and
hda2 for data file

what should I do about the Disk2? --I mean, do I need to parse the Disk 2 into corresponding hdb1 and hdb2? Or the RAID system will automatically parse Disk 2 and make it mirror Disk 1?

Thanks to help.

Scott

Re: RAID 1 and Linux Disk Partition

Patrick Terlisten — Mon, 14 Nov 2005 02:55:09 GMT

Hello Scott,

do you have a hardware-raid (Smart-Array) or software-raid (MD Device Driver)?

If you use a hardware-raid the two disks build one RAID-1 array. If you create partitions on that RAID-1, both partitions will be mirrored. If you use a software-raid, you got a MD-Device (/dev/md0). In this case, you need to create two partitions on that device.

Regards,
Patrick

Re: RAID 1 and Linux Disk Partition

scott_417 — Mon, 14 Nov 2005 15:57:03 GMT

Thanks for the response.

Does this mean, though there are two disks in RAID 1, the Linux sees or treated them as one device--correct? If so, I just take them as if I only have one hard drive and do the partition such as hda1 (for OS), hda2 (for log files), etc. --right?

Thanks to help.

Scott

Re: RAID 1 and Linux Disk Partition

Ivan Ferreira — Mon, 14 Nov 2005 18:50:17 GMT

Scott, you should post your question in just one cathegory. You will get answers anyway, but the answers will be organized.

When you create a raid, the OS sees only one device. You don't need to worry about the disks, you only need to work when one disk fails.

Re: RAID 1 and Linux Disk Partition

Patrick Terlisten — Tue, 15 Nov 2005 02:52:12 GMT

Hello Scott,

if you have a hardware-raid (two disks connected to a Smart-Array controller and configured as RAID 1), you see only one (virtual) disk. On that disk you can create your partitions. Try the following command:

fdisk /dev/ida/c0d0

Regards,
Patrick