Badboy Posted November 13, 2019 Share Posted November 13, 2019 (edited) Hi everybody, I have (4 - 10 TB) drives and (1 - 10 TB ) parity drive. I'm just curious, at what point or number of drives should I consider having a second parity drive? I know I'm a ways off from worrying about that just yet. Is there a general rule? Edited November 13, 2019 by Badboy Quote Link to comment
JorgeB Posted November 13, 2019 Share Posted November 13, 2019 There's no general rule, depends on a number of things: -how many disks -size of the disks -how important is the data -existence of backups I generaly have single parity on servers with up to 8 disks, dual parity for with more than 8 disks, but I have at least one full backup of every server. Quote Link to comment
Badboy Posted November 13, 2019 Author Share Posted November 13, 2019 7 minutes ago, johnnie.black said: There's no general rule, depends on a number of things: -how many disks -size of the disks -how important is the data -existence of backups I generaly have single parity on servers with up to 8 disks, dual parity for with more than 8 disks, but I have at least one full backup of every server. Hi Johnnie, Let's just say these 4 10TB drives are full and the data is important. As of right now would this one parity drive be ok? I do backup most of this data on a small Qnap and additional desktop drives. At some point I'm going to move the backup drives to the Unraid server, I want to consolidate everything into one for better transfer speeds and save on power. I use a Thermaltake case which can house 20 drives. Quote Link to comment
JorgeB Posted November 13, 2019 Share Posted November 13, 2019 If you have backups of at least most of it I would say 1 parity is OK for now, but with such high capacity disks I would go for dual parity at around 6 data disks. Quote Link to comment
itimpi Posted November 13, 2019 Share Posted November 13, 2019 It is important that you continue to keep backups of important data regardless of the number of parity disks. Parity protects against disk failure, but it does not protect against other potential causes of data loss. Quote Link to comment
JonathanM Posted November 13, 2019 Share Posted November 13, 2019 20 minutes ago, Badboy said: At some point I'm going to move the backup drives to the Unraid server, I want to consolidate everything into one for better transfer speeds and save on power. That's not an ideal move. If you have an incident that takes out multiple drives, you could easily lose both the primary data and all your backups. Quote Link to comment
JorgeB Posted November 13, 2019 Share Posted November 13, 2019 At some point I'm going to move the backup drives to the Unraid server, I want to consolidate everything into one for better transfer speeds and save on power. That's not an ideal move. If you have an incident that takes out multiple drives, you could easily lose both the primary data and all your backups. Yes, I missed that part of your post, dual parity adds redundancy, it's not a substitute for backups, you're much better off with single parity and backups than dual parity and no backups, I was recommending dual parity with 6+ plus disks + backups. Quote Link to comment
Badboy Posted November 13, 2019 Author Share Posted November 13, 2019 Not going to attach those drives to the raid. Going to add them as unassigned devices. Quote Link to comment
JorgeB Posted November 13, 2019 Share Posted November 13, 2019 10 minutes ago, Badboy said: Not going to attach those drives to the raid. Going to add them as unassigned devices. It's fine if you disconnect them when not in use, or e.g. a PSU problem can fry all the drives connected. Quote Link to comment
Badboy Posted November 13, 2019 Author Share Posted November 13, 2019 7 minutes ago, johnnie.black said: It's fine if you disconnect them when not in use, or e.g. a PSU problem can fry all the drives connected. That's a very good point!!! Didn't think about that. I shut my Qnap down after backups because I don't use it for anything anyway. I will just have to remember to disconnect when finished with the backups. Thanks for the feedback, appreciate it. Quote Link to comment
Badboy Posted November 13, 2019 Author Share Posted November 13, 2019 21 minutes ago, Badboy said: That's a very good point!!! Didn't think about that. I shut my Qnap down after backups because I don't use it for anything anyway. I will just have to remember to disconnect when finished with the backups. Thanks for the feedback, appreciate it. With the number of drives you have, do you spin them down when not in use? I never have, my thought it is more wear an tear on starting them backup. Even my desktops I never shut them down, might put them into sleep mode. Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.