Ubuntu Servers :: RAID5 - Re-adding Drive As Active, Not Spare?
Jan 13, 2011
I have a little nice Ubuntu server with 6x 1TB drives assebmbled into a RAID5 array. Recently SATA cable of one of the drives failed. So I ordered a new cable and ran the server in degraded mode for a few days. Like this:
Code:
/dev/md0:
Version : 00.90
Creation Time : Sat Sep 19 10:39:11 2009
Raid Level : raid5
Array Size : 4883812480 (4657.57 GiB 5001.02 GB)
code....
I'd like the 6th drive to be active, not spare, like before. Should I just wait for rebuild to be finished (it can easily take over 1 day)? Or should I add it somehow differently to be active immediately?
I'm not sure, but I think as I simulated failures unplugging one of the disk, after plugging it in again, the "failed" drive was active again and rebuilding was started as well of course. But it was 2 years ago, so...
The array works just fine for now - I can access files, etc. But I suspect, that in this state if another cable or drive fails, it won't survive anymore. Even after rebuilding is finished, but the 6th drive stays is still marked as "spare". Right?
I've been playing with this for hours, and have been unable to figure it out. I tried to convert my RAID5 array of 4 active disks and 1 spare to a RAID6 with 5 active disks.
I did this:
Code: mdadm --grow /dev/md4 --raid-devices 5 --level 6 Here is what I have on /dev/md4:
Code: /dev/sde1 active /dev/sdg1 active /dev/sdj1 active /dev/sdf1 active removed /dev/sdh5 spare code....
but it tells me that /dev/sde is busy, and then that it has a bad superblock (From what I've read, I'm sure the bad superblock is just because of the "busy" message). I've tried this with the -f option, too, with no luck.
Could any RAID gurus kindly assist me on the following RAID-5 issue?I have an mdadm-created RAID5 array consisting of 4 discs. One of the discs was dropping out, so I decided to replace it. Somehow, this went terribly wrong and I succeeded in marking two of the drives as faulty, and the re-adding them as spare.
Now the array is (logically) no longer able to start:
mdadm: Not enough devices to start the array.Degraded and can't create RAID ,auto stop RAID [md1]
Code: mdadm --create --assume-clean --level=5 --raid-devices=4 /dev/sda2 /dev/sdb2 /dev/sdc2 /dev/sdd2 As I don't want to ruin the maybe small chance I have left to rescue my data, I would like to hear the input of this wise community.
When i try to join my Ubuntu server to Microsoft Active Directory domain, i get the error message below.
Kinit failed: Clock skew too great Failed to join domain: Time difference at domain controller I know the reason is because of the time difference between my domain controller and the Ubuntu server. But what i want to know is that possible to join a domain without time synchronisation? Because my domain controller is working for another time zone, for another Country, so i can not synchronise it with my Ubuntu server.
As the title says, I have a failed RAID5 hard drive. What's the easiest way I can go by replacing it? I've seen many ways to do this, but I would like to know what other people are saying about this, and see how you would do it.
I'm convinced that mdadm is going to be the death of me. I've wasted numerous hours on this so far without luck.
OpenSuse 11.4 on an old Supermicro box, creating a software RAID1 array across 2 x IDE 500GB disks. Creating /dev/md0 as a 250MB partition across /dev/sda1 and /dev/sdd1 for /boot, another 465GB partition across /dev/sda2 and /dev/sdd2 as an LVM partition to hold volumes for the various other OS filesystems. After the initial installation and configuration there were a series of mishaps with faulty IDE cables that had drives failing to show up at boot. Somehow, /dev/sdd2 got configured to array /dev/md1 as a spare drive. And nothing I've done so far gets it to show up as an active drive.
The obvious step of failing the partition, removing it, then adding (or re-adding) will bring it back as a spare. I've tried roughly a dozen different permutations of those same steps. The latest was to 'dd if=/dev/zero of=/dev/sdd2' to clear the partition. Thought this might be the trick - after the zero, mdadm -E /dev/sdd2 reported 'no superblock' and no md1 configuration.
So 'mdadm --add /dev/md1 /dev/sdd2' and it still comes back as a spare. Here is mdadm -D /dev/md1
/dev/md1: Version : 1.0 Creation Time : Sat Jul 9 10:26:01 2011 Raid Level : raid1 Array Size : 488119160 (465.51 GiB 499.83 GB) code....
I can't stop this array, the OS is running from there. I can't easily boot from CD to repair, all IDE ports have disks attached.
Does anyone have an incantation to promote a spare to active?
so I setup a raid ten system and I was wondering what that difference between the active and spare drives is ? if I have 4 active drives then 2 the two stripes are then mirrored right?
I need some help on this one. I added an second internal hard drive to my file server, a 500GB WD. I want to use this drive as the primary storage drive for my file server, and I want to format it with XFS. I've found some guides showing me how to add hard drives, but they didn't really fit what I want to do. When I run fdisk -l this is what I get
Code:
Disk /dev/sda: 120.0 GB, 120034123776 bytes 255 heads, 63 sectors/track, 14593 cylinders Units = cylinders of 16065 * 512 = 8225280 bytes Disk identifier: 0x0001af4f
[code]....
Disk /dev/sdb doesn't contain a valid partition table
how to setup an Active/Active Load Balanced and High Available (If one of the nodes is down the system still runs) MySQL cluster. I have found quite a few howto's but I have some things unclear in my mind. I found a few solutions like this one: [URL] or this: [URK] Those are using two or four MySQL nodes, two Load Balancers to avoid a single point of failure but only one MySQL cluster management server. What happens if the MySQL cluster management fails?
I have also found a "MySQL Master-Master Circular Replication" technique but from what I read, with this option there is a chance that conflicts will arise if node A and node B both insert an auto-incrementing key on the same table.
I'm currently studying about LVM because of the snapshot features. I notice that most tutorials that I have read involves a spare hard drive or unused partition. I don't have a spare hard drive or unused partition on my server but I still have disk space if ever it was possible to do the snapshot on the same LVM partition.
is it possible to do snapshot on the same LVM partition?
been trying to get a spare computer up and running with 10.10 server 64bit no dice so far, after hours of memchecks, disk checksums, re-burns and whatnot..install stops at 73% and does f. all.. tail log shows that it stops at updating sources, alt+f2 and ps aux shows apt-get update process running. if I kill this process, I can continue with the installation, but for this I need to repeat same process - killing all the apt instances that show up - so that it can complete the install. Unacceptable imho. computer is a AMD cpu based, athlon 2 435 on an ASUS M4A89TD PRO mainboard. ddr3 4gb crucial ram sticks. drives are functional S-ATA. No external GPU, so using IGP.
Tried installing without eth-cable plugged in, with it plugged in, with a usb install (that sorry excuse for an install was even worse, "please insert cd" midway) I know I can get the install going with desktop version.. But why would I want an xserver running on a headless computer. Kind of pissed atm, spent so many hours at this, figuring it just might be a faulty HW item. It isn't. using 10.10 desktop on my laptop and production pc - and been using 8.04 as main server, until now...
Edit: another one of them optiarc sony nec **** for brains dvd/cd-rom/writer it seems. add a check for this in future releases, with big bold letters "YOU ARE SCREWED, BUY NEW HARDWARE" printed as soon as the cd loads in these drives.. I've got better things to spend my time on than staring at a screen trying to figure out why it won't load properly
To test stability, I rebooted the system, but on reboot, the array wasn't assembled correctly. Basically it had one device in "md_d2000", as a spare. So I stopped that device with
I don't have any important data on the array yet ... so I zero'd the superblocks on all devices, deleted the partitions, and started over .. here I go again:
3 new 1.5TB HD. 1 used 1.5TB hd with 980MB of data. I want to set up a raid 5 with a hot spare. I have music, pictures, videos, and movies (About 2.8TB worth). I have had a mismatch of drives previously, 250GB, 2 320GB, 500GB, 2 1TB and now a 1.5TB all with data. I have removed the one 250 and 2 320s and put the data on the 1.5TB that is currently installed.
What I would like to do is create a raid5 with the three new 1.5TB HD's, copy the data over from the currently installed 1.5TB and then grow or add that drive as a hot spare. Or just add it and then add another 1.5TB down the road as a hot spare don't know for sure.
In addition since I have 2 1 TB drives, I could add 2 more (Good deals on 1 TB drives right now) and have a total of 4 1TB drives. Could I have 2 raid5's (4-1TB's and 4-1.5TB's)in two separate arrays? I really do not know if that makes sense or not but here comes LVM. I am tired of managing my HD space and since i have multiple folders (Movies, music, pictures, videos) and within the movies folder I have R, G & PG folders for the ratings of the movies. (Pwd protect the R so the kids can't get to it) So with LVM installed with the Raid5 I should be able to create my folders and just keep adding data and not worry about moving folders around when I grow the storage by adding new drives. Is that correct? Maybe someone could point me to a how to.
Also, if I create 2 arrays (And I need to know so I can order the 2 additional 1TB drives), then I could put all the music, G and PG content on the one array and all the R and spicy stuff on the other and password protect it.
I recently installed a new home backup server with Ubuntu 9.10 x86_64 using the alternate CD. I used the CD's installer to partition my disk and created a software RAID 5 array on 4 disks with no spares. The root file system is located outside the raid array.
At first the array performed nicely but as it started to fill up, the io performance dropped significantly to the point where I get a transfer rate of 1-2MB/s when writing!
Created my own file server/nas, but get stuck in a problem after couple of months. I have a server with 4x 1,5tb disks, all connected to sata ports and 1 40gb ata133 disk running ubuntu 9.10 x64 amd. I've created a raid5 array using mdadm. It all worked great for couple of months but lately the raid5 array is degraded. disk sdd1 is faulting every few days. I have checked the drive but it is fine. If I re-add the disk and wait for 6 hours my raid5 array is all fine again, but after a few shutdowns, it is degraded.
my mdadm detail:
Quote:
root@ubuntu: sudo mdadm --detail /dev/md0 /dev/md0: Version : 00.90 Creation Time : Mon Dec 14 13:00:43 2009 Raid Level : raid5
I have ubuntu server 10.04 on a server with 2.8ghz 1gb ddr2 with the os on a 2gb cf card attached to the IDE channel and a software raid5 with 4 x 750gb drives. On a samba share using these drives I am only getting around 5 MB/s connected via wireless N at 216mbps and my router and server both having gigabit ports. Is a raid 5 supposed to be that slow? I was seeing speeds of anywhere from 20-50MB/s from other people and am just wondering what i am doing wrong to be so far below that.
I'm a bit at a loss on this one. I couldn't get a drive from a former RAID5 array to format. I did a dd to write zero's to the drive and attempted to fsck only to be stopped every time with the error: Couldn't find ext2 superblock, trying backup blocks.. fsck.ext3: Bad magic number in super-block while trying to open /dev/sda1
Smartctl shows no problems with the drive (a Seagate 750GB), but I haven't removed it and thrown it in a windows machine to do seagates proprietary drive diagnostics yet. Running Centos5.6 .I've never had this problem before. The drive is not mounted and the old md device has been removed as far as I can tell. It could still be attempting to assemble the RAID5 with the 1 drive, but I didn't see it attempt to do so.
I've built a server with (intentionally) very low-power components. The motherboard uses a Via C3 CPU running at 700MHz. The server has 512MB of RAM and I'm running 8.04 Server Edition (no GUI). This is purely a file server - not a lot of daemons started (except the defaults) -- no web server, etc. Just NFS, Samba and Open SSH (for remote administration). I'm not sure how much free RAM it has (it's down at the moment).
Is the RAM/CPU going to be inadequate for running software RAID5? I've done some big rsyncs and even without RAID, this thing is pretty slow. I'm not terribly concerned about the write speed, but if the read performance is going to be inadequate for playing (not streaming - just playing) a 720p MKV movie over my LAN, then I need to rethink this.
My fileserver initially had 3 1TB drives in RAID 5 configured with mdadm as /dev/md1. (System root is a mirrored raid on /dev/md0) I went to go add a 4th 1TB drive to /dev/md1 and grow the raid 5 accordingly. I was initially following this guide: [URL] but ran into issues on the 3rd and 4th commands. I've been trying a few things to remedy the issue since, but no luck. The drive seems to have been added to /dev/md1 properly, but I can't get the filesystem to resize to 3TB. I also am not entirely sure how /dev/md1p1 got created, but it appears to be the primary partition on the logical device /dev/md1. Relevent information:
The filesystem originated as ext3, I believe its showing up as ext2 in some of these results because I disabled the journal when doing some initial troubleshooting. Not sure what the issue is, but I didn't want to blindly perform operations on the filesystem and risk losing my data.
I have software raid 5 array, each time I reboot my server, I have to rebuild array again. Rebuilding array takes too long. I am using ubuntu server 10.10.
I also get sent to a Busybox (initramfs) shell with no text editor and don't know how to copy all the error messages and post them here. If there is a way, let me know. I've typed it out in the meantime:
Code: md0 : inactive sdxxxx Attempting to start the RAID in degraded mode... mdadm: CREATE user root not found mdadm: CREATE group disk not found
[Code].....
This is with a 3 disk RAID5 array. I turned off the system, pulled out a drive, and started it back up. Fresh install, all I've done so far is apt-get update and upgrade.
I've got a new Ubuntu 10.04 server install with a new 3 disk RAID 5. The boot disk is separate, not part of the RAID. I was trying to practice what I would do if a disk died to recover the RAID, so I unplugged one of the three disks. The machine now just hangs on startup. It shows fsck at the top of the screen but doesn't got anywhere from there. If you press a key it shows the Ubuntu splash screen. If I plug the disk back in, everything boots up normally. So, my question is, how do I get the machine to boot with one of the RAID members missing? I know I can recover it using the Live CD, but it would be nice to be able to get back into the machine without the CD.
I'm a light linux user over the last couple of years and I decided to built a HTPC/NAS device.
Setup: 40gb ide -> usb boot drive 3x2tb sata (4k Sector) drives
I've got another 2tb identical drive but it's holding data that is going to be copied to the raid after it's up and running and then be 'grown' into the raid array to yield a final 5+tb array. I tried doing a disk util raid array and it ended up failing after reboot due to it using the /dev/sd* designations and they swapped. I have no idea how to do the UUID version, my googlefu and practical guide to ubuntu. So I decided to do it manually in order to also fix the sector issue as disk util wasn't formatting them correctly and once formatted wouldn't let me create a raid array from the discs.
I am trying to build a file server with RAID 5 over a couple of 1TB HDDs, to serve about 10 client machines using Ubuntu Server. I already own a 22-port switch: HP ProCurve v1810G-24 Switch (J9450A), which I am assuming will do the job. And for the actual server I am thinking of buying: HP ProLiant DL120 1U. Will this hardware suffice, or am I missing something important to get the whole thing running?
I am setting up a new server and am in the midst of testing RAID. This is an Ubuntu 9.10 server. RAID1 (/dev/md1) is spread across 12 one-terabyte SCSI disks (/dev/sdi through /dev/sdt). It has four spares configured, each of which are also one-terabyte SCSI drives (/dev/sdu through /dev/sdx). I have been following the instructions on the Linux RAID Wiki ([URL]....
I have already tested the RAID successfully by using mdadm to set a drive faulty. Automatic failover to spare and reconstruction worked like a champ. I am now testing "Force fail by hardware". Specifically, I am following the advice, "Take the system down, unplug the disk, and boot it up again." Well, I did that, and the RAID fails to start. It outright refuses to start. It doesn't seem to notice that a drive is missing. Notably, all the drive letters shift up to fill in the space left by removing a drive. The test I did was to:
[code]....
Is removing a disk from the bus a reasonable test in the first place? Meaning, is this likely to happen in a production environment by other means than a human coming by and yanking out the drive? Meaning, is there a hardware failure that would replicate this event? Because, if so, then I don't know how to recover from it.
Something weird happened last night and my raid5 failed. I am trying to re activate it and see if my data is dead or what. When I run mdadm -Asv /dev/md0 I get
Code: mdadm: looking for devices for /dev/md0 mdadm: cannot open device /dev/dm-1: Device or resource busy mdadm: /dev/dm-1 has wrong uuid. mdadm: cannot open device /dev/dm-0: Device or resource busy mdadm: /dev/dm-0 has wrong uuid. mdadm: cannot open device /dev/sde2: Device or resource busy mdadm: /dev/sde2 has wrong uuid. mdadm: cannot open device /dev/sde1: Device or resource busy mdadm: /dev/sde1 has wrong uuid. mdadm: cannot open device /dev/sde: Device or resource busy mdadm: /dev/sde has wrong uuid. mdadm: cannot open device /dev/sdd: Device or resource busy mdadm: /dev/sdd has wrong uuid. mdadm: cannot open device /dev/sdc: Device or resource busy mdadm: /dev/sdc has wrong uuid. mdadm: cannot open device /dev/sdb: Device or resource busy mdadm: /dev/sdb has wrong uuid. mdadm: cannot open device /dev/sda: Device or resource busy mdadm: /dev/sda has wrong uuid.
I opened GParted to create a new partition on a new drive. He wanted me to create a partition table first which I did, and it was created directly without any prompt like im used to see when creating partition. So I recognized too late, that i actually created a MBR on one of my 6 1TB raid5 drives. Not beeing sure if the ne MBR was really written, I have opened ubuntu disk utility and clicked on the check raid button. It directly made a resync. After the resync, mdadm --detail /dev/md0 told me everything is ok and synced. Then I wanted to mount it with:
mount /dev/md0 /mnt Then I get the following error: "mount: wrong fs type, bad option, bad superblock on /dev/md0, missing codepage or helper program, or other error In some cases useful info is found in syslog - try dmesg | tail or so" I think I just killed my raid5 ;(
I shouldnt work on my server when im tired and when I actually have no time ;( My last hope is the fact, that "Disk Utility" shows that there is a .0 TB ext4 volume on my raid (see screen below) [URL]
I'm trying to find out which one is safer when it comes down to recovery process in case of a drive failure
A RAID5 created in mdadm or a Stripe RAID created on pure LVM
the RAID is purely for data storage for a SAMBA server, the OS will reside on its own drive.Ideally the RAID physical hard drives should be re-build on another machine in case of catastrophic server failure (mother board problem, or any other random problems as an example)I can't decide which of the 2 software RAID method is more convenient and safest, don't care about performance, it'll be a dedicated server for mass storage, it's going to mirror other 3 file servers on fakeRAIDs (dmraid), it's simply a redundant backup for the backups
The important goal here is portability.from what've read it appears that LVM might be more portable?but according to some dated (2009) info the mdadm seems to be a bit buggy when it comes to rebuilding the array, yet LVM doesn't appear that safe either which one would you pick for ease to rebuild on catastrophic failures?