ZFS is a modern file system and volume manager originally developed by Sun Microsystems and licensed under the CDDL. It is a copy-on-write file system with support for large storage arrays, protection against corruption, snapshots, clones, compression, deduplication and NFSv4 ACLs. An open-source ...

learn more… | top users | synonyms

5
votes
1answer
75 views

Is the size reported by `zfs send` exact or estimated?

Consider the following command and the output: zfs send -Pvi \ tank/vms/langara@zfsnap-2016-05-11_00.00.00--1w \ tank/vms/langara@zfsnap-2016-05-13_00.00.00--1w \ | dd > /dev/null ...
4
votes
1answer
463 views

ZFS on LUKS not recognized at boot

I've got 6 physical drives in RAID-Z2, which I intend to one-by-one convert to dm-crypt devices. My process was roughly: dd if=/dev/zero of=/dev/sdf Create keyfile /etc/crypttab.d/crypt-1.key ...
4
votes
1answer
789 views

ZFS ARC size vs target size

I am trying to understand the inner workings of the ZFS ARC. However, I am confused with several things: actual (zfs:0:arcstats:size) vs target size (zfs:0:arcstats:c). I understand that actual size ...
3
votes
1answer
112 views

ZFS: good read but poor write speeds

I'm in charge of downloading and processing large amounts of financial data. Each trading day, we have to add around 100GB. To handle this amount of data, we rent a virtual server (3 cores, 12 GB ram)...
3
votes
1answer
133 views

ZFS on Centos - “No such pool or dataset” and “devices is currently unavailable”

I'm trying to create zpools on CentOS 7 (3.10.0-327.10.1), and the zpool command seems to hate "wwn-0x" IDs. "zpool status" is clear - there are no zpools currently configured on the machine. I have ...
3
votes
1answer
193 views

Ubuntu 14.04 blk_update_request I/O error on same sector across all drives with ZFS

I'm running Ubuntu 14.04 with ZOL version v0.6.5.4: root@box ~# dmesg | egrep "SPL|ZFS" [ 34.430404] SPL: Loaded module v0.6.5.4-1~trusty [ 34.475743] ZFS: Loaded module v0.6.5.4-1~trusty, ZFS ...
5
votes
0answers
448 views

Using ZFS head node as database server?

I'm using a dual-head ZFS-backed NAS for high availability cluster shared storage, based on Nexenta's recommended architecture as seen here: The disks in 1 JBOD will store the database files for a ...
3
votes
0answers
321 views

zpool import one or more devices is currently unavailable

zfs drives from a FreeNAS that wouldn't power up after a move. Pulled the disks, scrapped the box, now I can't import any pools. I've tried zfs on Linux and freeNAS from shell on my laptop (using usb/...
3
votes
0answers
331 views

What ZFS file structure to use for zfs-root linux system?

In ZFS, you can build your filesystem hiearchy to include different fs-attributes per filesystem. For insance, compression in one area, no-exec/suid in others, noatime. For example, a HOWTO for ...
2
votes
0answers
44 views

ZFS on linux with centos 7.2 sync reads slow to crawl when executing sync writes

We are running ZFS on linux with centos 7.2. The array has 26 6tb Seagate sas drives in a mirrored configuration and then stripped across the mirrors to form our pool. 128gb arc, 480GB l2arc PCI ...
2
votes
0answers
101 views

Expanding JBOD with SAS extenders

My project is expanding 24-HDD ZFS box by adding 45-drive box with option to add another 45-drive box later (all are JBODs). Host box (24 HDDs) is Supermicro with single port expander backplane and ...
2
votes
0answers
38 views

Grow ZFS pool to use the whole disk

What's the (if there's any) way to grow a zfs pool that only uses a disk partially to use the whole disk? Background is, zfs is used here on a virtual machine and the Virtual machines disk has been ...
2
votes
0answers
81 views

ZFS - zfs destroy snapshot during zfs send incremental

How does zfs handle destroying snapshots during an incremental send? Example: 2 servers using ZFS: zfshost1 [root@zfshost1~]# zfs list -t snapshot NAME zones/40e66d56-4ea8-11e5-885d-feff819cdc9f@...
2
votes
0answers
36 views

Can I force nfsd on Solaris to announce more free space than physically available?

I'm working with various Solaris based distributions (OmniOS, SmartOS, Nexenta) and I have a highly compressible and deduplicable data set on a very small amount of high performance storage. The ...
2
votes
0answers
358 views

ZFS on RedHat configuration

I have to set up a ZFS storage appliance (Oracle ZFS Storage ZS3-2) with NFSv4. The NFS is mounted on a Redhat 6.5 cluster, where the linux users are created (they don`t exist on the appliance). ...
2
votes
0answers
118 views

How do I get Ubuntu to forget about a destroyed zfs pool?

I have also asked this question over on Ask Ubuntu but I thought I'd try here as well. The details can be found at: http://askubuntu.com/questions/304822/how-do-i-get-ubuntu-to-forget-all-about-an-old-...
2
votes
0answers
507 views

Can't remove zfs log device from pool

I run a FreeBSD 9.0 server with ZFS pool version 28 and ZFS version 5. I had two pools with a log on ssd's two partitions. These pools was created on FreeBSD 8.2 with ZFS pool version 15, and ZFS ...
1
vote
0answers
31 views

ZFS restarts resilvering over and over again. Also very slow

Here's one of my Solaris 10 servers after a couple of disk replacements in a zpool pool: volume state: ONLINE status: One or more devices is currently being resilvered. The pool will ...
1
vote
0answers
53 views

How to enable space reclamation from KVM guest to ZFS zvol iSCSI target?

I have a ZFS volume "tank/kvm/webhosting", exposed through iSCSI (using tgt) to KVM guest. <disk type='block' device='disk'> <driver name='qemu' type='raw' cache='none' io='native' ...
1
vote
0answers
27 views

ZFS issue after enlarging image

I created a new img using the following command: truncate -s 250G disk.img and I replace the existing image that I used for zpool with that one using (lxd.img was 2G): zpool replace lxd lxd.img ...
1
vote
0answers
21 views

Does zfs send scrub the sent data?

To my knowledge ZFS as a filesystem checks for data errors during each access to the data. I would therefore assume that it actually performs something like a scrub before sending the data thereby ...
1
vote
0answers
40 views

Why ZFS ARC hit rate is higher than real performance hit?

We've got Debian Wheezy host with ZFS on Linux with in. It is used only for serving large files over http. User activity is mostly characterized by a lot of random read. We've noticed that ~95% ARC ...
1
vote
0answers
140 views

ZFS copy on write

I am planning to use ZFS for backups. 5-10 servers will "stream" updates via DRBD to very large files (500 gigabytes each) on ZFS file system. The servers will generate about 20 megabytes per ...
1
vote
0answers
107 views

Missing free space in new zfs raidz2 zpool?

I'm running Nas4Free 10.2.0.2 - Prester (revision 1814) which is based on FreeBSD 10.2-RELEASE-p2 #0 r287260M: Fri Aug 28 18:38:18 CEST 2015. System has 24 GB memory. I've tried with ashift=9 and 12 ...
1
vote
0answers
43 views

ZFS SAN boot - what makes the OS crash during SAN switch change

I have a Solaris 10 server - with ZFS SAN boot - the OS pool has disks configured from two different HBAs c1 , c2 - have LUNs from different FA ports on the SAN array - c1 , c2 HBAs are connected ...
1
vote
0answers
103 views

zfs pools unavailable, disks shared with other pools

My ZFS pool called data do not mount anymore after a shutdown. Maybe there was some automatic update on the computer. I Don't know. zpool status returns no pools available zpool import returns ...
1
vote
0answers
339 views

ZFS (Solaris 11) - SAS controller died & was replaced - pool is suspended

(Note I will amend with zpool status for clarity, when I return to the server) I have a 6x2TB disk raidz2 ZFS pool which I am hosting in Solaris 11 My original M1015 (flashed to IT mode) installed 2 ...
1
vote
0answers
245 views

GlusterFS and ZFS snapshots

I know many people are using GlusterFS on top on ZFS. I'm wondering about snapshots: how do you ensure snapshot homogeneity among the nodes? I mean if you do a snapshot on a node, how can you be sure ...
1
vote
0answers
262 views

NexentaStor 3.1.5-GA (community ed) won't boot from a CD

I can boot from 3.1.5-GA ISO into a VirtualBox VM. But when I boot from a bootable CD, it stops at "Grub Stage2", and then drops me into a grub rescue shell after a few seconds.. I know very well how ...
1
vote
0answers
553 views

ZFS: Why does resilvering go over all disks in a pool rather than only those in the raidz1 vdev?

I'm wondering why Solaris is reporting action: Wait for the resilver to complete. scan: resilver in progress since Sun Jul 14 02:42:44 2013 24.9T scanned out of 39.2T at 54.9M/s, 75h46m to go ...
1
vote
0answers
50 views

partitioning a 2x larger disk to house zfs migration

so there are numerous sites taking about using vdevs made from disk partitions like this in order to reorder vdevs of different sizes. however, i have the following physical disks: Disk /dev/sda: ...
1
vote
0answers
398 views

Freenas - Expanding volume

We currently have a server with 5x3TB disks configured as a RAIDZ: zpool status pool: raid-5x3 state: ONLINE scrub: none requested config: NAME STATE ...
1
vote
0answers
305 views

Solaris x86 11.1 and qlt driver — only 3/4 ports attach

I'm using the QLogic QLE2564 4-port 8Gb HBA. The problem I have is that when I attach the qlt target mode driver to the card, only 3/4 ports attach the driver. ffffc10006854e58 pciex1077,2532, ...
1
vote
0answers
132 views

Accidentally resilvered 2 drives

We had 2 failed drives in our ZFS raidz1 pool. One had been resilvered to a spare and another was just out. The pool was in degraded mode. I replaced both drives and began the resilver on the non-...
0
votes
0answers
18 views

Best topology for mirrored data servers in GlusterFS

I am currently laying out the topology for a GlusterFS cluster, which is expected to grow pretty fast. Therefore, scalability and resiliency are key in this regard. The topology I've come up with is ...
0
votes
0answers
28 views

Best practice for setuid and setgid in /root and user directories

ZFS allows to created datasets with setuid turned off, which (AFAIK) means that setuid bit can't be set on files stored in those datasets. Assume now that there are two datasets, one for the /root ...
0
votes
0answers
25 views

ZFS Snapshot showing unreachable inside snapdir

I am using ZFS with Linux 3.19.0-58-generic. I have created some snapshots, but when I cd into these directories after one point it becomes unreachable, what does that mean ? Is there any workaround ...
0
votes
0answers
42 views

ZFS mirror migrated to other system with dd -> zpool import fails

I'm pretty new to ZFS and this might be an easy problem (but I don't find any discussions about how to do this): I've messed up a FreeBSD installation on a Root-on-ZFS mirrored ZFS Pool on a ...
0
votes
0answers
83 views

ZFS tuning for SSD queue depths

When using SSD on ZFS, what is the best configuration for the vfs.zfs.vdev.max_active parameters? As I know the default of this parameters is 1000, I don't have the intention to change this, but these ...
0
votes
0answers
167 views

ZFSonLinux : process stuck in D state, iowait for CPU 100%, HDD idle

I have a problem that occurs regularly,cca every 5 seconds. the rtorrent process gets stuck on disk wait D state for approx. 1-2 seconds,then continues with full speed. Sometimes the hangs take ...
0
votes
0answers
43 views

Wrong permission when accessing ZFS snapshot over NFS (Solaris server, Ubuntu client)

TL;DR: I don't understand why I can access one file but not an other (in the same directory), although they appear to have identical permissions. I have an NFS server running Solaris 10 10/08 and a ...
0
votes
0answers
117 views

Xenserver 6.5 (Open Source) VDI per ISCSI LUN (ZFS ZVOL)

In Xenserver 6.5 (open source edition) I want to create VMs with VDIs that are actually iSCSI LUNs shared by a CentOS 7 SAN which are in fact ZFS ZVOLS (the last part should not matter). My problem ...
0
votes
0answers
33 views

ZFS and controller level mirroring

If there are more than one SCSI controllers on your machine - there are disks from each controller - is there an option within ZFS to create a mirror of an existing pool so that sub mirror is picked ...
0
votes
0answers
41 views

Destroying zfs dataset, migrating data to parent dataset

I have these zfs datasets: pool1 pool1/ds_parent pool1/ds_parent/ds1 pool1/ds_parent/ds2 pool1/ds_other I want to keep all data which is now contained in the datasets ds1 and ds2, but I don't want ...
0
votes
0answers
113 views

Solaris 10 Update 8, ZFS boot/root zpool and moving disks around

One of my OLD machines is running solaris 10 Update 8 (x86). It has a mirrored ZFS I use for "root zpool". Both disks are failing so I plugged a new disk in a USB port and attached the new disk to ...
0
votes
0answers
84 views

ZFS - Reconnecting a disconnected but fully intact disk

If a disk gets disconnected from a ZFS array, but the drive itself if totally fine, what happens when you reconnect it? For example, if I have a mirror of 2 drives, if one is disconnected, then ...
0
votes
0answers
267 views

ZFS on Linux denied access when accessing child dataset on NFS

This is on 12.04 LTS with the latest ZFS on Linux from the ppa. I have two a storage pool named data, and a dataset data/Other with different settings (e.g. compression). I set data to sharenfs and ...
0
votes
0answers
178 views

zfs raidz can not read from disk

my freebsd 10 server running on zfs raidz. I have a problem with reading files, test dd of=/dev/null if=/tmp/test/1000mb.bin bs=1024k count=1000 953+1 records in 953+1 records out 1000000000 bytes ...
0
votes
0answers
1k views

Any disadvantage of running a virtual machine using files for its drives hosted on freenas/zfs?

I recently got tired of the really slow I/O reads and latency (10-30 MB/s read, not sure for latency but very slow) from a provider I rent a virtual machine from. He uses freenas, the virtual machine ...
0
votes
0answers
258 views

zfs recovery after hardware failure

My ZFS storage hardware failed including the rpool disks. I installed a new server and tried to import use zfs import -f poolname. I am able to see the pool and the disk utilized. But I am not able to ...