Linux查看文件系统的挂载时间浅析

我们在linux系统中如何找到文件系统的挂载时间呢,下面实验测试环境为rhel 6.6，其它linux版本没有验证测试。这个简单测试了一下常用的ext3/4、xfs、nfs文件系统。

 

 

ext文件系统

 

 

如果文件系统类型为ext3、ext4（ext2没有测试，这么老的文件系统也没有多少意义了），那么可以使用命令tune2fs查看文件系统最后一次挂载时间。如下所示：

 

[root@db-server ~]# tune2fs -l /dev/sda1

tune2fs 1.39 (29-may-2006)

filesystem volume name:   /boot

last mounted on:          <not available>

filesystem uuid:          582b189c-396c-4da8-a7a3-1effaa3e4000

filesystem magic number:  0xef53

filesystem revision #:    1 (dynamic)

filesystem features:      has_journal ext_attr resize_inode dir_index filetype needs_recovery sparse_super

default mount options:    user_xattr acl

filesystem state:         clean

errors behavior:          continue

filesystem os type:       linux

inode count:              26104

block count:              104388

reserved block count:     5219

free blocks:              88252

free inodes:              26070

first block:              1

block size:               1024

fragment size:            1024

reserved gdt blocks:      256

blocks per group:         8192

fragments per group:      8192

inodes per group:         2008

inode blocks per group:   251

filesystem created:       thu aug 11 14:28:18 2016

last mount time:          tue feb 12 15:36:22 2019

last write time:          tue feb 12 15:36:22 2019

mount count:              62

maximum mount count:      -1

last checked:             thu aug 11 14:28:18 2016

check interval:           0 (<none>)

reserved blocks uid:      0 (user root)

reserved blocks gid:      0 (group root)

first inode:              11

inode size:               128

journal inode:            8

default directory hash:   tea

directory hash seed:      b532c8d4-49b6-4d8a-a2e7-96a415daee37

journal backup:           inode blocks

 

 

如上所示，命令会输出last mount time这些信息。

 

 

xfs文件系统

 

如果文件类型是xfs的话，可以在日志/var/log/messages 中搜索xfs关键字。当然也可以搜索mounting关键字，具体测试如下所示：

 

[root@db-server ~]# grep xfs  /var/log/messages

jul 19 15:03:29 db-server kernel: sgi xfs with acls, security attributes, large block/inode numbers, no debug enabled

jul 19 15:03:29 db-server kernel: sgi xfs quota management subsystem

jul 19 15:03:29 db-server kernel: xfs (sdb): mounting filesystem

jul 19 15:03:29 db-server kernel: xfs (sdb): ending clean mount

jul 19 15:17:39 db-server kernel: xfs (sdb): mounting filesystem

jul 19 15:17:40 db-server kernel: xfs (sdb): ending clean mount

[root@db-server ~]# umount /u04

[root@db-server ~]# date

fri jul 19 15:40:52 cst 2019

[root@db-server ~]# mount  -t  xfs  /dev/sdb  /u04

[root@db-server ~]# grep xfs  /var/log/messages

jul 19 15:03:29 db-server kernel: sgi xfs with acls, security attributes, large block/inode numbers, no debug enabled

jul 19 15:03:29 db-server kernel: sgi xfs quota management subsystem

jul 19 15:03:29 db-server kernel: xfs (sdb): mounting filesystem

jul 19 15:03:29 db-server kernel: xfs (sdb): ending clean mount

jul 19 15:17:39 db-server kernel: xfs (sdb): mounting filesystem

jul 19 15:17:40 db-server kernel: xfs (sdb): ending clean mount

jul 19 15:40:55 db-server kernel: xfs (sdb): mounting filesystem

jul 19 15:40:56 db-server kernel: xfs (sdb): ending clean mount

 

 

或者搜索mounting关键字，grep -ri mounting /var/log/* | more

 

[root@db-server ~]# grep -ri mounting /var/log/* | more

/var/log/anaconda.log:02:10:34,361 info    : umounting loopback /tmp/product-disk /dev/loop7

/var/log/boot.log:remounting root filesystem in read-write mode:  [  ok  ]

/var/log/boot.log:mounting local filesystems:  [  ok  ]

/var/log/boot.log:mounting filesystems:  [  ok  ]

/var/log/messages:jul 19 15:03:29 db-server kernel: xfs (sdb): mounting filesystem

/var/log/messages:jul 19 15:17:39 db-server kernel: xfs (sdb): mounting filesystem

/var/log/messages:jul 19 15:40:55 db-server kernel: xfs (sdb): mounting filesystem

[root@db-server ~]# 

 

 

其实，ext3、ext4 也可以搜索/var/log/messages, 例如可以使用下面命令（不同版本的linux可能有所不同，以实际情况为准）

 

grep ext4 /var/log/messages

 

 

 

nfs文件系统

 

 

如果文件格式是nfs的话，可以用命令 cat /proc/self/mountstats，通过age来判断，这个表示nfs挂载后的时间，单位为秒。

"age" that specified the time in seconds since the nfs volume was mounted.

 

cat /proc/self/mountstats命令会输出age信息，如下所示：

 

device xxx.xxx.xxx.xxx:/docker mounted on /docker with fstype nfs4 statvers=1.1

    opts: rw,vers=4.0,rsize=1048576,wsize=1048576,namlen=255,acregmin=3,acregmax=60,acdirmin=30,acdirmax=60,hard,proto=tcp,port=0,timeo=600,retrans=2,sec=sys,clientaddr=10.10.5.53,local_lock=none

    age:    23049075

    caps:   caps=0xffdf,wtmult=512,dtsize=32768,bsize=0,namlen=255

    nfsv4:  bm0=0xfdffbfff,bm1=0xf9be3e,bm2=0x0,acl=0x3,pnfs=not configured

    sec:    flavor=1,pseudoflavor=1

    events: 933485 16418086 98 204 247406 29 32837386 50 0 303 0 32337916 494048 30 8084851 56 0 8084831 0 2 46 0 0 0 0 0 0

    bytes:  6359097360 190907 0 0 233464 182715 303 48

    rpc iostats version: 1.0  p/v: 100003/4 (nfs)

    xprt:   tcp 839 0 1 0 19 1983681 1983681 0 4743991 0 37 2150 2760316

 

但是个人测试发现，有些版本的nfs，输出信息是没有age。如下截图所示（client nfs v3:）