search for: raidzn

The default blocksize is 128K. If you are using mirrors, then each block on disk will be 128K whenever possible. But if you''re using raidzN with a capacity of M disks (M disks useful capacity + N disks redundancy) then the block size on each individual disk will be 128K / M. Right? This is one of the reasons the raidzN resilver code is inefficient. Since you end up waiting for the slowest seek time of any one disk in the vdev, and w...

...rays in a pair is out of service for an extended time, the remaining array can still withstand a drive failure. Well, I''d like to get rid of that hardware RAID5 and use RAIDz... but then that would preclude my mirroring setup from happening since I can''t set up two distinct RAIDZn sets within a pool and mirror them. For those familiar with ZFS internals, could a "RAIDZ+1" configuration be a distinct possibility? /dale

"Does raidzN actually protect against bitrot?" That''s a kind of radical, possibly offensive, question formula that I have lately. Reading up on theory of RAID5, I grasped the idea of the write hole (where one of the sectors of the stripe, such as the parity data, doesn''t get written - le...

Folks, We are in the process of purchasing new san/s that our mail server runs on (JES3). We have moved our mailstores to zfs and continue to have checksum errors -- they are corrected but this improves on the ufs inode errors that require system shutdown and fsck. So, I am recommending that we buy small jbods, do raidz2 and let zfs handle the raiding of these boxes. As we need more

In a discussion a few weeks back, it was mentioned that the Best Practices Guide says something like "Don''t put more than ___ disks into a single vdev." At first, I challenged this idea, because I see no reason why a 21-disk raidz3 would be bad. It seems like a good thing. I was operating on assumption that resilver time was limited by sustainable throughput of disks, which

Hi all, I would like to knwon if with ZFS it''s possible to do something like that : http://tldp.org/HOWTO/LVM-HOWTO/removeadisk.html meaning : I have a zpool with 48 disks with 4 raidz2 (12 disk). Inside those 48 disk I''ve 36x 3T and 12 x 2T. Can I buy new 12x4 To disk put in the server, add in the zpool, ask zpool to migrate all data on those 12 old disk on the new and

Hi all I''m seeing some rather bad resilver times for a pool of WD Green drives (I know, bad drives, but leave that). Does resilver go through the whole pool or just the VDEV in question? -- Vennlige hilsener / Best regards roy -- Roy Sigurd Karlsbakk (+47) 97542685 roy at karlsbakk.net http://blogg.karlsbakk.net/ -- I all pedagogikk er det essensielt at pensum presenteres

The time has come to expand my OpenSolaris NAS. Right now I have 6 1TB Samsung Spinpoints in a Raidz2 configuration. I also have a mirrored root pool. The Raidz2 configuration should be for my most critical data - but right now it is holding everything so I need to add some more pools and move some data around. To start I need a vdev I will call "temp" that acts as a networked bit

Hello all, I understand that relatively high fragmentation is inherent to ZFS due to its COW and possible intermixing of metadata and data blocks (of which metadata path blocks are likely to expire and get freed relatively quickly). I believe it was sometimes implied on this list that such fragmentation for "static" data can be currently combatted only by zfs send-ing existing

Hi I know some of this has been discussed in the past but I can''t quite find the exact information I''m seeking (and I''d check the ZFS wikis but the websites are down at the moment). Firstly, which is correct, free space shown by "zfs list" or by "zpool iostat" ? zfs list: used 50.3 TB, free 13.7 TB, total = 64 TB, free = 21.4% zpool iostat: used

Hi, I wanted to add a disk to the tank pool to create a mirror. I accidentally used zpool add ? instead of zpool attach ? and now the disk is added. Is there a way to remove the disk without loosing data? Or maybe change it to mirror? Thanks, Martijn -- This message posted from opensolaris.org

Hi All, I am looking at ZFS and I get that they call it RAIDZ which is similar to RAID 5, but what about RAID 10? Isn''t a RAID 10 setup better for data protection? So if I have 8 x 1.5tb drives, wouldn''t I: - mirror drive 1 and 5 - mirror drive 2 and 6 - mirror drive 3 and 7 - mirror drive 4 and 8 Then stripe 1,2,3,4 Then stripe 5,6,7,8 How does one do this with ZFS?