zpool import FreeBSD 7.3S - BBS

系統是FreeBSD 7.3S主要是我有一顆硬碟全部割給ZFS格式
POOL name是MailBackup

但是下指令卻找不到，很奇怪

[/root] -root- zpool status
pool: MailBackup
state: ONLINE
scrub: none requested
config:

NAME STATE READ WRITE CKSUM
MailBackup ONLINE 0 0 0
da3p1 ONLINE 0 0 0

errors: No known data errors

17:52 [/root] -root- zpool import MailBackup
cannot import 'MailBackup': no such pool available

17:53 [/root] -root- uname -sr
FreeBSD 7.3-STABLE-201008

17:53 [/root] -root- gpart show
=> 34 2147483581 da3 GPT (1.0T)
34 2147483581 1 freebsd-zfs (1.0T)

17:57 [/root] -root- zfs get all
NAME PROPERTY VALUE SOURCE
MailBackup type filesystem -
MailBackup creation Mon Aug 18 15:24 2014 -
MailBackup used 676G -
MailBackup available 324G -
MailBackup referenced 676G -
MailBackup compressratio 1.00x -
MailBackup mounted no -
MailBackup quota none default
MailBackup reservation none default
MailBackup recordsize 128K default
MailBackup mountpoint /MailBackup default
MailBackup sharenfs off default
MailBackup checksum on default
MailBackup compression off default
MailBackup atime on default
MailBackup devices on default
MailBackup exec on default
MailBackup setuid on default
MailBackup readonly off default
MailBackup jailed off default
MailBackup snapdir hidden default
MailBackup aclmode groupmask default
MailBackup aclinherit restricted default
MailBackup canmount on default
MailBackup shareiscsi off default
MailBackup xattr on default
MailBackup copies 1 default
MailBackup version 3 -
MailBackup utf8only off -
MailBackup normalization none -
MailBackup casesensitivity sensitive -
MailBackup vscan off default
MailBackup nbmand off default
MailBackup sharesmb off default
MailBackup refquota none default
MailBackup refreservation none default
MailBackup primarycache all default
MailBackup secondarycache all default
MailBackup usedbysnapshots 0 -
MailBackup usedbydataset 676G -
MailBackup usedbychildren 53.1M -
MailBackup usedbyrefreservation 0 -

看的到poll，但是問題是無法import 回來。

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