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4

What they're alluding to here is a configuration where you simply add all the disks to a pool (without a parent mirror or raidz group controlling the disks). In this configuration, the number of devices a file is put on is dictated by the copies attribute, which is controlled by the zfs set command - so some data (by ZFS filesystem) in the pool will have ...


3

These paragraphs are misleading and misinformed. Ari has a single disk workstation. She buys a new disk and plugs it in. ZFS automatically adds the new disk space into the pool. ZFS doesn't automatically add a newly inserted disk to a pool. You have to run the zpool command to tell how you want the disk to be used. Her home directory is mirrored ...


2

As you have no common baseline snapshot in your setup, you will not be able to perform an incremental zfs send any longer. You would need to destroy the dataset in backuppool: zfs destroy -r backuppool/x and re-send the most recent snapshot to backuppool zfs send mainpool/x@6 | [transfer magic] | zfs recv backuppool/x The deleting of all your backup ...


2

Without detailed explanation here is how you can do this. Create an archive of your LXC container. Create a Proxmox Container using that archive as a template. First cd into your lxc container root directory: cd /var/lib/lxc/debian8/rootfs/ (If you used an lvm volume as your containers storage, you need to mount it and cd into your mount point, which ...


2

As tegbains pointed out in a comment, zfs send streams do not benefit from any storage-level deduplication in place. They also don't benefit from any other settings; this is why zfs send | zfs receive can be used to migrate data to new settings that otherwise would only take effect once the data is rewritten -- such a enabling or disabling deduplication, or ...


2

Do not do this. I repeat: Do not do this! You will get cluster headaches out of this. If metadata changes in meantime, it could cause crashes and/or invalid data returned. These filesystems are not designed to work like this. Do not use them that way. This is especially bad idea with ZFS. If you really have to, use something very very basic, without ...


2

Why are you passing the disks through a RAID Controller? JBOD would make more sense when using ZFS. You could run into Problems because of your controller. Anyway, its save to just detach and re-attach the disk. You could also try to replace the disk (without really replacing it: zpool replace pool disk) Let it resilver and scrub again.


2

Solaris 11 ZFS uses NFSv4 ACLs rather than POSIX ACLs. Linux doesn't have NFSv4 ACLs on ZFS at all, and seems like it never will. While NFSv4 ACLs are a superset of POSIX ACLs, seems like only Solaris can transfer/translate POSIX ACLs to NFSv4 ones during file moving/copying. So, concluding, I don't see a way to preserve ACL in ZFS snapshots. Either use ...


1

I read on the freebsd forums a post which suggested to use zfs online -e <pool> <vdev> (without needing to offline the vdev first) This ultimately was the solution, but it required that ZFS autoexpand be disabled first: [root@timestandstill ~]# zpool list NAME SIZE ALLOC FREE CAP DEDUP HEALTH ALTROOT dfbackup 214G 207G ...


1

EDIT: i first thought it was mirror pool, not raidz. Firstly, zpool replace should work fine. If it is slow because that dying disk is acting slow, you can offline/detach it first so data is rebuilt from other disks and reads are not attempted from the bad disk. Multiple failing disks is not a good thing though. Exporting pool, using ddrescue and then ...


1

More RAM might be a good option. If read performance is not critical, but metadata operations are: I would recommend setting "primarycache" to "metadata" for your filesystems. If you have SSDs for L2ARC, you can also choose to use memory (ARC) for caching "all" and secondarycache (L2ARC) as "metadata". Please note that the other way around does not work ...


1

Use one or the other. I suggest using /etc/exports for consistency and readability, especially if your NFS server is serving data from non-ZFS filesystems.


1

I suspect the ATA driver is retrying the read operation a couple of times when it receives an error before passing the error back to the filesystem driver. What this means is by the time the ZFS filesystem driver gets the result of the read the data is all there, and correct, but it likely took a bit longer than normal to happen. There is of course no error ...


1

patched within ZFS on Linux: https://github.com/zfsonlinux/zfs/pull/3404 get the git version and compile it: git clone https://github.com/zfsonlinux/zfs.git


1

I found that I as I had been experimenting with cache settings to see what would happen I had left the primary cache switched off which can result in real IO being far greater than logical IO due to [application] reads a file, gets 4k (pagesize?) of data and processes it, then it reads the next 4k, etc. ZFS, however, cannot read just 4k. It reads ...


1

Please make sure the zfs service (target) is enabled. That's what handles pool import/export on boot/shutdown. zfs.target loaded active active ZFS startup target You should never have to struggle with this. If you have a chance, run an update on your zfs distribution, as I know the startups services have improved over the last few releases: ...


1

I'd say yes. My rule is to stay under 87% on SSD-only pools when using drives that haven't been heavily over-provisioned. The SSD use case introduces the drive endurance component, while the random write latency is less of an issue that with spinning disks. Either way, regardless of disk choice, why would you intentionally plan to run your workloads at ...


1

The most simple solution is to periodically flush buffer and pagecache memory. You can do it easily running a similar bash line in the background (or in another tty): while true; do echo 3 > /proc/sys/vm/drop_caches; sleep 5; done UPDATE: as it seems that the above solution does not work as needed, you can try a different way to avoid polluting the ...


1

Given the fact, that the zpool loss took place during a regular reboot, I hoped that at least the zpool export took place. And even if it had been shut down unclean, I prefer to do rescue works on copies. So I added a large HDD to my system (which was added as device sdb - thanks udev) and formatted it with two partitions of the same size as the zfs ...



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