set zfs’s property snapdir to hidden or visible see snapshot directory
2 minute read
背景
zfs的snapshot, 以往我们可以通过clone或者rollback来查看snapshot的内容. 当然不推荐rollback, 因为会导致zfs回退.
其实还有一种方法来查看snapshot的内容, 那就是设置zfs的snapdir属性,
如果开启了这个属性的话, 可以直接在zfs目录的.zfs中查看对应的snapshot的内容.
默认snapdir=hidden, 所以.zfs是不可见的.
修改成visible后, .zfs目录可见.
[root@db-172-16-3-150 zpp]# zfs set snapdir=visible zpp/test
[root@db-172-16-3-150 test]# zfs get all zpp/test|grep snapdir
zpp/test snapdir visible local
[root@db-172-16-3-150 test]# zfs get all zpp/test
NAME PROPERTY VALUE SOURCE
zpp/test type filesystem -
zpp/test creation Tue May 27 16:31 2014 -
zpp/test used 86K -
zpp/test available 63.3M -
zpp/test referenced 30K -
zpp/test compressratio 1.00x -
zpp/test mounted yes -
zpp/test quota none default
zpp/test reservation none default
zpp/test recordsize 128K default
zpp/test mountpoint /zpp/test default
zpp/test sharenfs off default
zpp/test checksum on default
zpp/test compression off default
zpp/test atime on default
zpp/test devices on default
zpp/test exec on default
zpp/test setuid on default
zpp/test readonly off default
zpp/test zoned off default
zpp/test snapdir visible local
zpp/test aclinherit restricted default
zpp/test canmount on default
zpp/test xattr on default
zpp/test copies 1 default
zpp/test version 5 -
zpp/test utf8only off -
zpp/test normalization none -
zpp/test casesensitivity sensitive -
zpp/test vscan off default
zpp/test nbmand off default
zpp/test sharesmb off default
zpp/test refquota none default
zpp/test refreservation none default
zpp/test primarycache all default
zpp/test secondarycache all default
zpp/test usedbysnapshots 56K -
zpp/test usedbydataset 30K -
zpp/test usedbychildren 0 -
zpp/test usedbyrefreservation 0 -
zpp/test logbias latency default
zpp/test dedup off default
zpp/test mlslabel none default
zpp/test sync standard default
zpp/test refcompressratio 1.00x -
zpp/test written 18K -
zpp/test snapdev hidden default
[root@db-172-16-3-150 ~]# zfs snapshot zpp/test@1
[root@db-172-16-3-150 ~]# cd /zpp/test
[root@db-172-16-3-150 test]# ll
total 0
[root@db-172-16-3-150 test]# touch a
[root@db-172-16-3-150 test]# zfs snapshot zpp/test@2
[root@db-172-16-3-150 test]# touch b
[root@db-172-16-3-150 test]# zfs snapshot zpp/test@3
[root@db-172-16-3-150 test]# ll -la /zpp/test/
total 4
drwxr-xr-x 2 root root 4 May 27 16:33 .
drwxr-xr-x 3 root root 3 May 27 16:31 ..
-rw-r--r-- 1 root root 0 May 27 16:33 a
-rw-r--r-- 1 root root 0 May 27 16:33 b
dr-xr-xr-x 1 root root 0 May 27 16:31 .zfs
[root@db-172-16-3-150 test]# cd .zfs
[root@db-172-16-3-150 .zfs]# ll
total 0
dr-xr-xr-x 2 root root 2 May 27 16:33 shares
dr-xr-xr-x 2 root root 2 May 27 16:33 snapshot
[root@db-172-16-3-150 .zfs]# cd snapshot/
[root@db-172-16-3-150 snapshot]# ll
total 0
dr-xr-xr-x 1 root root 0 May 27 16:33 1
dr-xr-xr-x 1 root root 0 May 27 16:34 2
dr-xr-xr-x 1 root root 0 May 27 16:34 3
[root@db-172-16-3-150 snapshot]# cd 2
[root@db-172-16-3-150 2]# ll
total 1
-rw-r--r-- 1 root root 0 May 27 16:33 a
[root@db-172-16-3-150 2]# cd ../3
[root@db-172-16-3-150 3]# ll
total 1
-rw-r--r-- 1 root root 0 May 27 16:33 a
-rw-r--r-- 1 root root 0 May 27 16:33 b
