Dear all,

This questions is about LVM2 + RAID 1, and whether I should worry about the setup I have made. I have recently setup a server (Ubuntu) for the cluster of our research group. The system consists out of 2x2=4 harddisks.

The first two harddisks were combined using RAID 1 (except for boot + swap). This set of harddisks is mainly for programs and the operating system. The second set of harddisks was also completely combined using RAID 1, and was meant for the home folders, data storage and other repositories.

Subsequently I have created a LVM partition on the first RAID array and a second LVM partition on the second RAID array. Then the necessery logical volumes were created for linux and other data we want to store on the server.

Offcourse, crucial data is frequently backed up to an external server.

I chose for this setup because in case of single disk failure, I could do a rebuild of the RAID 1 array and restore everything again to normal. I chose for LVM because for some partitions, I could not foresee what sizes would be most appropriate. LVM allowed me to change these sizes later on.

But now, after I have installed all this, I am reading all these unpleasant stories about broken RAID1-LVM2 setups, and a high degree of difficulty of retrieving data.

Was I wrong in assuming that in case of harddisk failure, I cannot simply rebuild the RAID array with a new disk ?
Offcourse I always have the external backup, but I chose this setup because I thought I could still easily restore my system in its original state after disk failure... Is this indeed the case, or not ?
If I would chose to re-install my complete server, what would be easiest to restore in case of HD failure ? LVM2 mirror or RAID 1 ?

Thanks in advance

Coen

Your config sounds fine to me. I've done the same thing you have, had a disk crash, then successfully replaced it. No problems. The only potential problem I see is with /boot. I keep a copy of that in the unused/unmirrored space on the second disk. If I ever need to use it, I'll have to play minor games with grub and fstab.

What problems are you concerned about.