Tag Info

Hot answers tagged

11

Much has happened since I asked this question in October 2010. As of September 2013, a new collaboration known as OpenZFS will serve as a central site for several ZFS projects. The new site is http://open-zfs.org/ (with a dash) Today at LinuxCon North America, Brian Behlendorf and Matthew Ahrens are announcing that members from the illumos, zfsonlinux.org, ...


11

To change the properties (be it compresson, deduplication or checksumming) of already written data, the zfs approach is to run the data through a zfs send | zfs receive sequence. Obviously, you do not need to offline the system for that, but you will need enough resources in your zpool / on the system to hold two dedup'ed copies of the data set in question ...


9

This is a udev issue that seems to be specific to Debian and Ubuntu variants. Most of my ZFS on Linux work is with CentOS/RHEL. Similar threads on the ZFS discussion list have mentioned this. See: scsi and ata entries for same hard drive under /dev/disk/by-id and ZFS on Linux/Ubuntu: Help importing a zpool after Ubuntu upgrade from 13.04 to 13.10, device ...


6

$ sudo find /lib/modules/$(uname -r)/updates -name "splat.ko" -or -name "zcommon.ko" -or -name "zpios.ko" -or -name "spl.ko" -or -name "zavl.ko" -or -name "zfs.ko" -or -name "znvpair.ko" -or -name "zunicode.ko" | xargs rm -f $ sudo apt-get install --reinstall ubuntu-zfs $ sudo apt-get install --reinstall $(dpkg-query --show --showformat='${binary:Package}\n' ...


6

IMHO the parameters in /sys/module/zfs/parameters can only be set to 0 / 1 - disabled / enabled. I am in the same boat wanting to limit zfs' memory usage and it seems one has to create a /etc/modprobe.d/zfs.conf file and enter the parameter and the desired value in there. E.g. options zfs zfs_arc_max=34359738368 source: ...


5

First off, it's worth stating that ZFS is not a supported filesystem for MongoDB on Linux - the recommended filesystems are ext4 or XFS. Because ZFS is not even checked for on Linux (see SERVER-13223 for example) it will not use sparse files, instead attempting to pre-allocate (fill with zeroes), and that will mean horrendous performance on a COW ...


5

I hate to say this, but do you know that you were basically adding unraided disks to your pool? The command you provided basically says, "Add another disk to pool nas and stripe it with the existing disks." Is that what you meant to do? The pool is done at this point, especially if anything was written to the bad disk. If this were a pair of mirrors, the ...


5

This came up in discussion on the ZFS mailing list. The kernel ABI changed between 0.6.2 and 0.6.3 in such a way that 0.6.3 user-land tools can't interact with 0.6.2 kernel modules, which is the configuration after upgrading to 0.6.3. According to numerous messages on this list, the right approach is simply to reboot. This is covered in the ZFS ...


5

That looks like...a bug. In fact, it is a bug. The ZFS userland is updated, but the kernel modules aren't being updated by DKMS. This assertion is caused by the version mismatch. You can work around it by a process given in a comment to the bug, by removing the old kernel modules and then reinstalling everything. $ find /lib/modules/$(uname -r)/extra -name ...


5

Scrub your pool again (if you haven't already): zpool scrub zstorage That error is telling you that inode <0x9f115> is corrupt (deleting the file broke the filename->inode mapping, so it's just reporting the inode now). Either something still has the file open or the metadata just needs to be cleaned up (which a scrub should do). To clear the error if ...


5

Oracle officially killed OpenSolaris, so the website will not be updated anymore. FreeBSD is working with the IllumOS project to advance ZFS at this point (their website is still a bit scant on details). I don't know if these changes are derived from actual Solaris 11 development or not, nor if the changes will be merged into the official project (a likely ...


4

The zfs mailing list remains on opensolaris.org, and Oracle has not established a new public website for their ongoing ZFS development project. Update (2013): The opensolaris.org website has now been shut down, and Oracle’s ZFS mailing list has moved to the new Solaris-ZFS.java.net website.


4

For versions up to 28, you can still browse the repository in OpenSolaris web site: http://src.opensolaris.org/source/history/onnv/onnv-gate/usr/src/uts/common/sys/fs/zfs.h http://src.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/uts/common/sys/fs/zfs.h#348 Update: This repository has moved to: ...


4

Everything is operating normally. You're running into TB vs TiB confusion. TL;DR 12TB raw == 10.8TiB raw (which is what is listed by zpool list) 7.5TB usable == 6.8TiB usable (which is what is listed by zfs list) You have: 3×3TB drives 2×1.5TB drives yielding a total of 12TB of raw storage. ○ → units 12TB TiB * 10.913936 / 0.091625969 ...


4

Instead of mounting zpool2 as /var/db, mount it as /zpool2 or /db or whatever makes sense for you. Then make /var/db a symlink to /db.


4

This may sound a bit crazy, but I support another application that benefits from ZFS volume management attributes, but does not perform well on the native ZFS filesystem. My solution?!? XFS on top of ZFS zvols. Why?!? Because XFS performs well and eliminates the application-specific issues I was facing with native ZFS. ZFS zvols allow me to ...


3

You can set the file system mountpoint properties to legacy and use /etc/fstab to define them. That way, you'll be able to define the order in which they will be mounted. Edit: I just noticed you already considered the legacy approach. It might be the only one though.


3

Ubuntu seems to have some annoying udev issues that we don't see on the Red Hat/CentOS side. I'd recommend using the WWN-based device names if you can, as they seem less susceptible to this. Have you seen: Why did rebooting cause one side of my ZFS mirror to become UNAVAIL?


3

If you ever end up on this page and your running Debian, you only have to do the following to fix the issue: # apt-get update # apt-get dist-upgrade # reboot The issue occurred because a simple update doesn't not replace old library files with the newer ones. This is why a dist-upgrade is needed. From the apt-get manpage: dist-upgrade in addition to ...


3

Your choice would likely have twoish aspects: data integrity and security performance When using different LUNs with ZFS, it will make implicit assumptions that the LUNs are separate physical devices, distributing reads and writes among them to optimize performance. You do not have to add more redundancy to the setup (i.e. you could just add your LUNs as ...


3

Run a regular script (cron) that checks zpool status -x output. Longer-term, the ZFS on Linux project is working towards this in the form of an event daemon. The Solaris-derived systems had access to the Fault Management Architecture. As far as automated reports, even commercial solutions like NexentaStor use scheduled checks. There's nothing wrong with ...


3

Try zfswatcher, it works really well for me.


3

I'll answer. You may be overthinking... Snapshots aren't backups. So if you're trying to protect against a compromise, you should go the extra step and back up to another device. Now, snapshots can be extremely helpful in producing a clean consistent copy of your data to ship or back up to another device. As far as ZFS on Linux, It's very easy to integrate ...


3

No, ZFS on Linux doesn't support native encryption. Another option is encryptfs, but at this juncture, you're not going to find a native solution.


3

Ugly, but this would work. Except when it doesen't;). Be very careful when specifying the partitions and when replacing the disks try it in am VM beforehand, setup the virtual disks like your hardware an dry run it 1 or 2 times. make a scrub before you start and take a look at the S.M.A.R.T info from the disks. You would not try this with an already ...


2

The official bug page has this fix for Ubuntu and Debian users: # apt-get update # apt-get dist-upgrade # reboot


2

Typically for folks using ZoL that want encryption, encryptfs isn't desireable because you lose both performance and fuctionality. ZFS works best when it is the filesystem, not when you layer others on top of it (again, you can, but it's suboptimal). This is what encryptfs does (layers an encrypted filesystem on top of ZFS), and exactly why you see so much ...


2

In the 1st case, maybe some files of user1 can't be discovered by find(1) because they're hidden by some fs being mounted on top of them? In the 2nd case, maybe something is mounted somewhere under the zfs1 mountpoint and you include that in the space calculation? Incidentally, zfs get -H -o value mountpoint zpool/zfs1 will print just the mountpoint, so ...


2

I'd stick with mainstream filesystems like XFS (as promoted by Red Hat) and rely on ZFS for advanced filesystem needs. This is mainly due to: Mindshare: ZFS knowledge is held in the Linux, FreeBSD and Solaris/OpenIndiana communities. Maturity: The ZFS codebase is proven and has been around for awhile. Best-practices have evolved and I can't recall seeing ...


2

A 2TB limit is not that uncommon, so you should stop thinking that you're being penalized more than most other setups in the world.. That being said - the most common way of doing this is to just stripe it (RAID 0) at the VM level. If you make sure that the SAN admin puts the LUNs on different controllers (if it's a active/active setup) you'll actually ...



Only top voted, non community-wiki answers of a minimum length are eligible