RAID1 or mirrored RAID uses two disk that have the same data.

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326 views

replacing failed hard disk in raid 1 on dell emc cx300 [closed]

how can I replace failed disk in slot 12 in raid 1 on san dell emc cx300 I HAD Configured the san with hot spare hard disk in slot 13. Is it enough to remove it from it's slot an put instead of it ...
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2answers
172 views

RAID 1 - IOPS Write Penalty 1 or 2

I keep seeing articles describing the RAID IOPS write penalty for RAID 1 (and RAID 10) as 2. RAID 0 would have a penalty of 1, of course, since every write is simply written to disk. RAID 1 is ...
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1answer
1k views

How to delete removed devices from a mdadm RAID1?

I had to replace two hard drives in my RAID1. After adding the two new partitions the old ones are still showing up as removed while the new ones are only added as spare. I've had no luck removing the ...
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2answers
2k views

Clonezilla is not able to clone a RAID 1 disk

I have a HP Server DL320 G5. There are two SATA hard disks configured as RAID 1 through HP embedded RAID controller. Server OS is running GNU/Linux (Fedora) Server booted up with clonezilla live CD. ...
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1answer
477 views

Various problems with software raid1 array built with Samsung 840 Pro SSDs

I am bringing to ServerFault a problem that is tormenting me for 6+ months. I have a CentOS 6 (64bit) server with an md software raid-1 array with 2 x Samsung 840 Pro SSDs (512GB). Problems: ...
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2answers
1k views

How to move RAID 1 to RAID 1+0

I have two HP disks in RAID 1 (300 Gb), and would like to at 2 additional disks in RAID 1+0 having in total of 600 Gb on C:. I would like to know is it possible to do it using Array Configuration ...
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2answers
816 views

ZFS: 3 devices: what's the difference between mirror and raidz2?

It would seem like with 3 devices, it's possible to configure a ZFS pool with either mirror or raidz2 mode. What's the difference in performance and reliability? (In regards to reliability, I'm ...
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2answers
95 views

Move CentOS to new raid1 hardware server

I have an existed CentOS server with a normal hard disks (2 disks sda,sdb). They very small. Now I want to update server with a RAID1 hardware and new 2 bigger disks (remove 2 old disk). How can I do ...
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1answer
58 views

Does RAID1 also checks for corruption? [closed]

I have two 1.5 TB disks, and I don't trust both of them because of weird noises and bad clusters. I was wondering if I put them in a software RAID1 array (mirrored volume in Win7) it will write my ...
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1answer
39 views

Access Server 2003 formatted HDD from W7 installation

I have a server problem, not sure what the best approach may be. The scenario is this: OS: Server 2003 The OS was on dedicated IDE drive; there are 2x1TB SATA drives which were in a Windows software ...
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0answers
162 views

Half of disk space missing on RAID1, all disks it seems to be ok

Hi there. I have a problem with raid array. I miss it a half. My disks layout is 2 x 250 gigabytes velociraptors (Array_0000) 2 x 1TB velociraptors (Array_0001) ....both connected in RAID1. OS ...
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2answers
482 views

Remake SW RAID1 from a new HDD and an old HDD with bad blocks

I have a SW RAID1 and I just replaced /dev/sda with a new HDD as the old one failed. Now, upon trying to recreate the RAID array I discovered that the "good" HDD (/dev/sdb) has bad blocks with prevent ...
0
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1answer
187 views

Saving data on a failing software RAID 1 setup

My CentOS 6 server is running a software RAID 1 configuration with two 1 TB disks. Yesterday trouble started happening when the server was very irresponsive. I checked the logs and noticed a whole ...
0
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1answer
349 views

RAID1 - Possible to recover failed drives?

PowerEdge 1850 has two physical hard drives, configured as RAID1. Accessing via DRAC 4/I I can see that both drives indicate Failed & Offline. However, the DRAC log indicates that both drives ...
2
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1answer
196 views

Concerns of simultaneous failure of SSD Raid1

Since SSD's have a write limit requiring wear leveling one would assume that all things being equal 2 identical SSD drives would wear nearly identically if they mirror data writes. When one drive ...
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1answer
2k views

DELL Server RAID Exception - Resyncing

Today they brought this old DELL server with 2 HDD initialized in RAID 1 Array. The server was used as a syslog aggregator for a long time and I was tasked to to some maintenance before we return the ...
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2answers
219 views

Possible to build a RAID 1 with only one drive with LSI 9260-4i? [closed]

I have a LSI 9260-4i RAID card plus 1x 300GB Drive. My issue is I have to ship out the server for the 2nd drive to be installed onsite. Can I configure a RAID 1 with only 1 drive, and plug in the ...
1
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1answer
84 views

Speed up RAID 1 drive read speeds

Sorry I don't know much about this stuff...we have been having issues with a slow server, very slow for users and when you access the server direct, we have added more RAM but it seems it may be a ...
3
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1answer
1k views

Linux RAID mdadm: what does 'Events' mean?

When I type mdadm --detail /dev/md0 I get a lots of useful information most of which I understand. However I also get a line that reads: Events : 0.710 Where the number varies. Naively, I ...
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2answers
259 views

Linux software raid fails to include one device for one RAID1 array

One of my four Linux software raid arrays drops one of its two devices when I reboot my system. The other three arrays work fine. I am running RAID1 on kernel version 2.6.32-5-amd64. Every time I ...
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1answer
61 views

Safest approach when designing storage server [duplicate]

We are planing cloud solution for our customers and we are really concerned with designing safest storage servers for their files. This storage won't be IO demanding, as it will contain only files ...
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2answers
185 views

Degraded drive in RAID1 Windows 2008 - system won't boot

I have inherited a Windows 2008 server setup with 2x 160GB Seagate boot drives and 2x Western Digital 1TB data drives. This is one of two servers inside a school. They are three years old and part of ...
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1answer
2k views

Replacing Hard drives/RAID array Dell Poweredge 2900

I have a Dell Poweredge 2900 that I'm upgrading from 4x SATA 250GB Drives in a RAID 5 situation to 2x SATA 1TB Drives in a RAID 1 situation. The box is running Windows Server 2003, with a PERC5/i ...
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1answer
129 views

RAID1: Can I do 'write-mostly' in hardware (LSI type cards) so Drive A: 100% READ and WRITE and Drive B: ONLY WRITE?

The Google hammer has failed me, so I turn to this august body for help :-) I'm interested in doing SSD/HDD RAID1 pairs using the principle of 'write-mostly' as available in Linux's software RAID ...
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1answer
361 views

RAID1 LVM, XEN and flashcache

I am regarding to question: Improving IO with FlashCache I have setup a RAID1 (/dev/md0) LVM (*/dev/vg_xen*) and executed following command: flashcache_create -p thru flashcache0 /dev/sdc /dev/md0 ...
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2answers
216 views

Something wrong with Linux software RAID1

I have a software RAID1 and now every week Linux synchronize my raid volume. I checked cat /proc/mdstat: *Personalities : [raid1] md3 : active raid1 sda5[0] sdb5[1] 1822445428 ...
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2answers
1k views

How to mount parition in from a working driver in RAID1

One of hard drives in array is dead, I'm unsure if it's raid0 or raid1, what I'm trying to achieve is mount the working drive and make a backup of what's left. If I mount /dev/md127 then I can see ...
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0answers
94 views

Reconfigure from Raid0 to Raid1, is it possible?

currently I have Fujitsu tx140 s1p servers, one Tower and one Rack. They are both running with the same hardware, configures the same way, so I'll just ask one Q for both. They have an motherboard ...
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3answers
204 views

mdadm raid1, drive failure lost 14days worth of data?

I am rather confused. One evening I had a server which had died. I went to reboot it and noticed it was stuck on the "GRUB" boot screen. I then noticed a hard drive had failed. I put a new hard drive ...
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1answer
352 views

“LV Status NOT available” after converting root from lvm2 to lvm2+raid1 (lvconvert --type raid1)

I just converted by lvm2 root filesystem from linear lvm2 (single HDD:sda) to lvm2 raid1 (using lvconvert -m1 --type raid1 /dev/ubuntu/root /dev/sdb5 command). But after this conversion I can't boot ...
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1answer
236 views

Replacement raid1 drive is one block smaller. What to do?

Apparently once should always leave a bit of empty space at the end of each raid1 partition. But if we're too late for that, what can be done if a replacement RAID1 drive is slightly smaller than the ...
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3answers
330 views

Raid 0, Raid 1, Raid 5, Raid6, Raid 10 Read/Write performance? [duplicate]

Assume a single disk has a baseline of 1W & 1R performance, how does the different RAID configurations behave? My initial guess: Raid 0: 2W 2R Raid 1: 1W 2R Raid 5: ? ? Raid 6: ? ? Raid 10: ...
0
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1answer
398 views

LVM mirror with data and logs mirrored on same 2 devices

I'm trying to set LVM mirroring with only 2 devices. It works perfecly when I add third device for mirrorlog, or use corelog. But with only 2 devices and --alloc anywhere LVM nearly always creates ...
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3answers
373 views

Rebuilding Raid-arrays

How I can rebuild raid arrays? I am using Raid 1. My datacentar says it needs to be fixed, first i thought it is HDDs faulty because of smartmoontools scanning result but it is not. command: cat ...
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1answer
1k views

Converting BTRFS filesystem to RAID1 fails with “Inappropriate ioctl for device”

I had a ~1.6TB BTRFS volume on a single partition, to which successfully I added another freshly created and formatted partition (on another device) of exact same size with the intent of mirroring ...
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2answers
516 views

mdadm: Which disk is being rebuilt?

I noticed my software RAID1 degraded, and wanted to figure out which of the two disks in the array is being rebuilt/re-synced since they both show as being up. I am hoping someone can shed some light ...
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1answer
59 views

raid 1 need to move folder in rescue shell

Good day All. I have a remote server running raid 1 which I connect to using ssh keys. I accidentally moved the /root/.ssh folder and need to put it back so I can log on again. The people I rent off ...
0
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1answer
203 views

removing software raid without data loss

i wonder if/how i can stop my linux machine using the installed software raid, without loosing any data. All information i found was about removing the superblock of any hdd, and this is o/c what i ...
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2answers
64 views

manually editing shadow file on disk from raid1 array

At work we have a machine to which root password has been lost. I have pulled out the disk and mounted it to another computer. Now I think the next step should be editing root password in the shadow ...
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2answers
3k views

mdadm raid 1 grub only on sda

I just finished setting up a CentOS 6.3 64bit server with mdadm however a lightbulb went on and I realised grub would only be installed on the first drive which is about as much use and an ashtray on ...
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2answers
2k views

DegradedArray event on /dev/md1

This morning I got this message: This is an automatically generated mail message from mdadm running on A DegradedArray event had been detected on md device /dev/md1. Faithfully yours, etc. P.S. ...
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5answers
340 views

Using RAID1 to assist in offsite backups

I'm trying to set up an offsite, offline backup procedure for my company's critical information. We already have an in-office redundancy backup set up using RSYNC that backs everything up onto two ...
0
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1answer
538 views

New HDD swap in SAS 6 ir shows it is missing?

SETUP: Dell Poweredge T410 with Windows Server 2003, SAS 6 IR Raid-1. Both the original drives were Dell Certified Seagate Barracudas for enterprise, 250gb. The new HDD is a Seagate Barracuda 500gb, ...
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317 views

Raid 1 and Latency

I am aware that RAID comes with certain write penalties, etc and that varies at different levels. I am trying to figure out how latency is affected in RAID 1. From my SAN, I can look at the number of ...
0
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1answer
205 views

Will Windows Server 2008 R2 software RAID volume with “Failed Redundancy” be available during resynching?

In addition to this question: Windows Server software RAID volume constant "Failed Redundancy" I have this problem on my production server too, but im concerned about resynching. If I ...
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1answer
1k views

SBS 2003 boot stalls at acpitabl.dat

I have a SBS 2003 server running for 3 year without any problems, and few days ago it freezes during the boot. System is using two 500 Gb drives in RAID1 (Intel Matrix 7.5) After trying to load in ...
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1answer
2k views

How do you set up RAID1 with both disks bootable on Debian/Ubuntu?

In Debian 6, new installation, what is the recommended way of setting up a software RAID1 array so that the system is bootable from both disks? I have heard that people that don't know what they are ...
2
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2answers
200 views

Copy entire filesystem in a folder where a raid-1 array is mounted

I am trying to migrate from a single disk drive system to a double disk drive software raid-1 system that already has a running system on it. Meaning that formatting and having a new installation of ...
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0answers
197 views

Raid1 disk degraded after reboot

I'm testing a Rackspace cloud server and have two Cloud Block Storage volumes set up in a Raid1 configuration. There are no system files on these volumes, they're purely for storage. Everything ...
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2answers
75 views

Ubuntu 9.10 won't reboot after replacing a failed drive

Hello Serverfault community. I hope someone can shed light on a peculiar problem I am having with an Ubuntu 9.10 server install. I am not a Linux expert but have the responsibility of fixing the box ...