RAID5 is not a backup.
RAID5 is not a backup.
RAID5 is not a backup.
RAID5 is not a backup.
RAID5 is not a backup.
RAID5 is not a backup.
RAID5 is not a backup.
RAID5 is not a backup.
I haven't said it enough times, but I hope someone who needs it will get this message before it's too late.
Someone who has had to troubleshoot 3 failed RAID5's in the last week in his dayjob
It's RAID time. I've started the server and I'm just having a look around before I start poking around with mdadm.
The RAID10 has 4x 3TB drives. The first two (sda, sdb) are WD Red CMR, The second two (sdc, sdd) are ancient WD Greens, that won't re-add to the array. The plan was to replace the Greens with more Reds.
SMART tests on all drives: No reallocated sectors, no sectors pending reallocation. The Greens aren't dead. This surprised me.
Sidenote: When interviewing people for IT jobs, I have a #RAID question.
In a 4-drive array, what is the most reliable solution: RAID6 or RAID 10?
The answer is RAID6, as you can lose any two drives. With RAID10, you can only lose two drives that aren't in the same mirror. (Yes, I know there's risks with vibration. That's why no RAID5.)
Once you get to 6 drives, the odds change, and RAID10 is statistically better.
Of course, for my own 4-drive array, I didn't follow my own advice.
I had bad déjà vu sleep last night after learning just yesterday about raids on #Seattle#queer bars over the weekend. (I organized the initial political response to the 2009 Atlanta Eagle #raid.)
Seeing media coverage today is making me feel a lot better, because the local community there is clearly fighting back.
We fought hard for our right to self-expression; #Stonewall was nearly 55 years ago now.
#Shaarli: How To Directly Read A Linux RAID 1 Member Disk | by Gy B. | Medium - Méthode pour lire un disque issu d'un RAID miroir sous Linux. mdadm insère au début du disque des métadonnées, donc il faut les ignorer... : https://medium.com/#lecture#disque#raid#miroir
In week 2 of my #SysAdmin class, we're talking about storage models and disks: DAS, NAS, SAN, Cloud storage, disk interfaces, #RAID, LVM, #ZFS, physical disks, and partition types and tables.
The exercises include spinning up #AWS#EC2 instances and filling up disk space, using up all inodes, and moving an EBS volume across different instances and OS.
Has anyone heard of a #Yottamaster 5 Bay #RAID External Hard Drive Enclosure #PS500RU3? I bought one cos I needed a local backup (I have an offsite) for my Synology DS1520+. I have 5-6 external disks I am (right now) plugging into a separate single USB3.1g2->SATA3 dock and running an rsync script on each of the 5 drives. Irritatingly slow w/swapping out drives. So I figured I'd get this to try out. I'm gonna try it in both "JBOD" mode and RAID5 hardware mode.
Mort de Mohamed Bendriss à Marseille: la version du Raid contredite par l’image
Touché par un tir de LBD en pleine poitrine, dans la nuit du 1er au 2 juillet, cet homme de 27 ans est mort d’une crise cardiaque. Les images des caméras de surveillance, d’une riveraine et de la #police, récupérées par Mediapart, permettent de reconstituer le face-à-face entre son scooter et la colonne du #Raid.
À Marseille, Abdelkarim Y. a bien été éborgné par un tir du Raid
Le 30 juin, cette unité d’élite déployée pour contenir les émeutes a tiré au #LBD dans l’œil gauche d’un homme de 22 ans. L’enquête judiciaire montre que deux policiers ont fait feu simultanément, à une cinquantaine de mètres de la victime. Le lendemain, le #Raid blessait mortellement son cousin, Mohamed Bendriss, avec la même arme.
This allows extra cursed shit like a an encrypted & RAID-5 running NTFS - Tho that won't be useable by anything but Linix and I disrecommend it almost as hard as mixing hardware RAID controllers and/or dmraid with ZFS.
Program crashed while you were modifying a mail? Who knows what the on-disk file looks like now. You had it git-versioned? Good. If all goes well and git or the computer itself doesn't crash while updating things, that might be enough.
Turns out, #LVM#RAID-1 with #dmintegrity over two separate physical disks and then putting a #dmcrypt device on top of the RAID is really slow. As in, it's estimating to take a week to do the initial sync on the two 12TB WD Red drives on SATA. (For comparison, zeroing out one of these disks should take 8 hours or something.)
Apparently it's a somewhat-known problem with dm-integrity, related to its journal.
How would you build something bitrot-safe & encrypted with that hardware? #Debian 12.
I have a Lacie 2big TB2 RAID enclosure that works perfectly well BUT only has 2x 3TB drives (in RAID 0, so 6TB - data safety is of no concern).
Question: Lacie's max supported drives are just 8TB. I'd love to go big with the Seagate Exos 20TB drives. Possible? Is it a hardware limitation of the controller chip or something? Or was 8TB simply the maximum when they last updated the compatibility chart?
Like with any #RAID and similar, it works best when the used drives are the same model, at least the same size and speed...
Specifically about your example: Do you have yet another drive for #swap? If not, I would suggest to create (identical!) partition tables on the drives (zpool on top of partitions is unproblematic with #FreeBSD) and have some swap space on both of them. That's better than putting swap in a file or on a zvol...
#Today I learned about the write_mostly flag, which lets you mark a device in a #Linux software #RAID to be... well, mostly used for writes. In other words, the driver will prefer all other drives for reading operations.
Very handy in my current "#CMR drive together with #SMR drive" situation. I marked the slower SMR drive as write_mosty and so while this drive is busy doing all the writes, the other drive can perform all the reads and STILL have enough time to perform its own writes.
#Kansas' top law enforcement agency will now lead the criminal investigation that led police in the city of #Marion to #raid a local #newspaper last Friday.