Zfs Notes

Simple commands

zfs list

zpool list

zfs get all <thing>

like

get all /mnt/tank/dataset_music

Compression

I'm pretty sure this has to do with high compression ratios set on the the zimbra backups volumes. I've lowered it before and it's gotten better, so I will lower it to gzip-3 form gzip-6. Let's see how this looks over the next week.

[root@sms-thumper /]# date ; zpool list tank ; zfs list -o name,type,volsize,quota,refer,avail,compressratio,usedbysnapshots,mountpoint -S refer
Mon May 13 10:46:39 EDT 2013
NAME   SIZE   USED  AVAIL    CAP  HEALTH  ALTROOT
tank  19.0T  15.4T  3.66T    80%  ONLINE  -
NAME                       TYPE        VOLSIZE  QUOTA  REFER  AVAIL  RATIO  USEDSNAP  MOUNTPOINT
tank/zimbra-msgstr-XX      filesystem        -     5T  3.61T  1.39T  1.38x         0  /tank/nfs/zimbra-msgstr-XX
rootpool                   filesystem        -   none    34K   385G  1.00x         0  /rootpool
rootpool/ROOT              filesystem        -   none    19K   385G  1.00x         0  /rootpool/ROOT
rootpool/export            filesystem        -   none    19K   385G  1.00x         0  /rootpool/export
[root@sms-thumper /]# zfs get compression tank/zimbra-msgstr-XX
NAME                   PROPERTY     VALUE     SOURCE
tank/zimbra-msgstr-XX  compression  gzip      local
[root@sms-thumper /]# zfs set compression=gzip-3 tank/zimbra-msgstr-XX
[root@sms-thumper /]# zfs get compression tank/zimbra-msgstr-XX
NAME                   PROPERTY     VALUE     SOURCE
tank/zimbra-msgstr-XX  compression  gzip-3    local
[root@sms-thumper /]#

zfs send

on freenas: http://doc.freenas.org/index.php/Replication_Tasks

replication

from: http://docs.oracle.com/cd/E18752_01/html/819-5461/gbchx.html

Receiving a ZFS Snapshot Keep the following key points in mind when you receive a file system snapshot:

Both the snapshot and the file system are received.

The file system and all descendent file systems are unmounted.

The file systems are inaccessible while they are being received.

The original file system to be received must not exist while it is being transferred.

If the file system name already exists, you can use zfs rename command to rename the file system.

For example:

# zfs send tank/gozer@0830 > /bkups/gozer.083006
# zfs receive tank/gozer2@today < /bkups/gozer.083006
# zfs rename tank/gozer tank/gozer.old
# zfs rename tank/gozer2 tank/gozer