2
votes
1answer
31 views

MD RAID sector repair

This article states that RAID controllers are smart about unrecoverable read errors, and try to rewrite such sectors with the redundancy of the component drives. If the sector is bad, the disk's ...
1
vote
0answers
38 views

Software-RAID with ext4 but without 64bit support

last year I set up a Software-RAID5 with 5x3TB yielding 12TB of usable capacity. Just today, needing more storage, I have finished growing the RAID to two more 3TB disks: Personalities : [linear] ...
0
votes
1answer
31 views

Raid1+0: create stripe over two /dev/mdx on partition or not?

Given that I haven't found a way to define how a Raid10 is created with mdadm, i went the Raid1+0 solution. How to display/define Mirror/Stripping pairs with mdadm mdadm --create /dev/md0 --level=1 ...
1
vote
1answer
66 views

How to display/define Mirror/Stripping pairs with mdadm

I want to make a standard linux software Raid10 over 4 HDD. The server has 4HDDs, 2 pairs from different vendors in order to avoid batch problems. I want to have the mirror over two different ...
0
votes
1answer
41 views

Linux MD Raid same device detection

Linux md raid driver delays recovery/verification of multiple devices if they share the same parent device. We have setup where disks are pationed via device mapper, they use bcache, etc.. and ...
1
vote
2answers
357 views

Remove a duplicate lvm physical volume uuid?

After upgrading a rhel 5 server today I rebooted to the new kernel: curr=2.6.18-371.el5PAE prev=2.6.18-348.18.1.el5PAE. In the boot sequence I saw a message indicating Logical Volume Management was ...
0
votes
2answers
387 views

Slow software raid with SSDs

We have moved a web application with an Oracle database to a new server because the old one was dying. The old server had two mirrored hard discs plus a separate non-mirrored SSD for the Oracle ...
0
votes
1answer
127 views

Is there anything I can do with a software RAID 1 on linux to workaround temporary 'bad' sectors?

Basically I have two identical hard disks that are in perfect working order, they just don't have the vibration tolerance they need for the environment they are in. (I am making an educated guess that ...
1
vote
1answer
170 views

HDD compatibility to rebuild for RAID

Last year we build a RAID 1 with Western Digital 2 TB drive model number WD20EARS. Unfortunately one of the drives failed. We are unable to find any new drives of the same model number. What do we do? ...
1
vote
1answer
91 views

Fresh setup: how to tell mdadm not to bother synchronizing the _data_? Or does it have to?

Two questions: how, if at all, can I tell mdadm that the freshly created array needs no synchronizing because there is no data on it? I.e. basically force it into a state where it assumes that the ...
2
votes
2answers
1k views

mdadm stalls rebuilding a RAID5 array at 99.9%

I recently installed three new disks in my QNAP TS-412 NAS. These three new disks should be combined with the already present disk into a 4 disk RAID5 array, so I started the migration process. ...
1
vote
1answer
113 views

Reshape linux md raid5 that is already being reshaped?

I just converted my RAID1 array to a RAID5 array and added a third disk to it. I'd like to add a fourth disk without waiting fourteen hours for the first reshape to complete. I just did this: mdadm ...
3
votes
2answers
571 views

Linux Software RAID1 Rebuild Completes, but after reboot, its degraded again

I have been beating my head with an issue here, and I'm now turning to the internet for help. I have a system running Mandrake Linux, with the following configuration: /dev/hda - This is a IDE ...
0
votes
2answers
355 views

Headless server with an mdraid array won't boot

I'm in a bit of a pickle. I have a headless server (Acer EasyStore) running Ubuntu 12.04.1, which, after an update, now refuses to boot. It has four disks, one of which holds the OS in a partition and ...
1
vote
0answers
106 views

What should I know before I set up RAID 6 on Linux?

I just ordered five 1TB drives to install as a RAID 6 array in a Linux server (keeping the existing 1TB drive as a boot disk). I want to use Linux MD for RAID rather than a RAID card, to avoid ...
5
votes
1answer
882 views

What effect does RAID stripe size have on read-ahead settings?

I'm trying to figure out the correct read-ahead values to set on a RAID10 array, and I'm wondering if the RAID stripe size should factor into my considerations. I've heard conflicting information ...
3
votes
3answers
290 views

Can I split one RAID1 partition in two?

I have a linux box with CentOS 6.2 and a RAID1 (2x 2Tb) configuration: /dev/md1 -> / (10G) /dev/md2 -> /home (1.9T) I want to split the md2 in two different partitions, so I can get the ...
4
votes
1answer
130 views

VERY peculiar permission masks, UIDs, GIDs and file names in Linux

I've just booted to find my software RAID 5 in Ubuntu not mounting. When trying to mount it gave me an NFS error (which was confusing). I ran fsck on /dev/md0 and my screen scrolled with fixes for ...
0
votes
0answers
982 views

Can't mount logical volume, RAID/MD/LVM problems

I have a file server with 48 2TB HDDs split across 2x 3ware 9650SE-24M8 RAID cards. Both cards have 24 drives in RAID 1+0. MD softraid is setup in raid 0 with the two RAID 1+0s making RAID 100. LVM2 ...
2
votes
1answer
731 views

Backup data from RAID 1 disk out of its server

I'm facing with a pretty easy problem in my opinion. I've extracted a working disk from a RAID1 and I'm looking to copy only data (FS and RAID configuration doesn't matter) into another location ...
2
votes
2answers
890 views

Move an existing RAID 5 array from Ubuntu to Gentoo

I have a 64-bit Ubuntu machine with a 4-disk RAID 5 using software raid (md). I've been able to boot an Ubuntu LiveCD and recognize the array with a simple mdadm -A /dev/md0. It was easy to mount ...
4
votes
2answers
2k views

Why does RAID5 with an odd number of data disks have poor write performance

According to the comments on my other question, it's more than possible that the reason my MD RAID array is performing poorly is because my RAID5 array has 5 data disks. I've tried searching for ...
2
votes
3answers
676 views

Linux boot: md raid FS not ready (sometimes)

Using Ubuntu 11.04 (latest patched) I have 5 RAID-1 file systems that are automatically assembled during the boot process (Note: none of the system FS /, /usr... are raid, only user FSes). Once in ...
1
vote
1answer
2k views

Linux software RAID that uses system RAM for write cache

Is it possible to configure software RAID 5 on linux that uses system RAM for write cache? I have a file server with 8GB of RAM ... would be really cool if I could dedicate 4GB to write cache. If ...
1
vote
1answer
161 views

Erratic write patterns with linux md RAID1

I'm experiencing strange write performance patterns on a RAID1 array of SATA disks. My kernel is vanilla 2.6.37 and my server has 32G RAM. I'm copying a 32G file from an XFS filesystem on a SAS drive ...