总结了一些自己喜欢的命令组合，好记也好敲

最佳命令组合：df -hT

# df -hT
Filesystem           Type   Size  Used Avail Use% Mounted on
/dev/mapper/vg_kashu-lv_root
                     ext4    18G  1.3G   15G   8% /
tmpfs                tmpfs  112M     0  112M   0% /dev/shm
/dev/sda1            ext4   477M   48M  405M  11% /boot
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# df -hTi
Filesystem           Type  Inodes IUsed IFree IUse% Mounted on
/dev/mapper/vg_kashu-lv_root
                     ext4    1.1M   31K  1.1M    3% /
tmpfs                tmpfs    28K     1   28K    1% /dev/shm
/dev/sda1            ext4    126K    44  125K    1% /boot
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# df -hTtext4
Filesystem           Type  Size  Used Avail Use% Mounted on
/dev/mapper/vg_kashu-lv_root
                     ext4   18G  1.3G   15G   8% /
/dev/sda1            ext4  477M   48M  405M  11% /boot
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可能会用到的命令

findmnt findmnt -text4 mount | column -t

最佳命令组合：du -sh /path

# du -sh /boot
45M     /boot
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# du -sh /* --exclude=/proc | sort -n
0       /sys
4.0K    /anaconda-ks.cfg
4.0K    /install.log.syslog
4.0K    /media
4.0K    /mnt
4.0K    /opt
4.0K    /selinux
4.0K    /srv
6.7M    /bin
12K     /install.log
14M     /sbin
16K     /lost+found
21M     /lib64
28M     /etc
36K     /home
45M     /boot
80K     /root
104K    /tmp
156K    /dev
241M    /lib
376M    /var
597M    /usr
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最佳命令组合：pstree -pauU | less

# pstree -pauU | less
init,1
  ├─atd,2718
  ├─auditd,2481
  │   └─{auditd},2482
  ├─console-kit-dae,2738 --no-daemon
  │   ├─{console-kit-da},2739
  ├─crond,2703
  ├─dbus-daemon,2519,dbus --system
  ├─dhclient,2248 eth0
  ├─dhclient,2436 -1 -q -lf /var/lib/dhclient/dhclient-eth0.leases -pf /var/run/dhclient-eth0.pid ...
  ├─hald,2553,haldaemon
  │   ├─hald-runner,2554,root
  │   │   ├─hald-addon-acpi,2596,haldaemon
  │   │   └─hald-addon-inpu,2586
  │   └─{hald},2555
  ├─login,2726
  │   └─bash,2804
  ├─master,2693
  │   ├─pickup,3196,postfix -l -t fifo -u
  │   └─qmgr,2707,postfix -l -t fifo -u
  ├─mingetty,2728 /dev/tty2
  ├─mingetty,2730 /dev/tty3
  ├─mingetty,2732 /dev/tty4
  ├─mingetty,2734 /dev/tty5
  ├─mingetty,2736 /dev/tty6
  ├─rsyslogd,2501 -i /var/run/syslogd.pid -c 5
  │   ├─{rsyslogd},2502
  │   ├─{rsyslogd},2503
  │   └─{rsyslogd},2504
  ├─sshd,2616
  │   └─sshd,2855
  │       └─bash,2857
  │           └─pstree,3210 -pauU
  └─udevd,424 -d
      ├─udevd,2181 -d
      └─udevd,2182 -d
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最佳命令组合：netstat -tunape 或 ss -tunap | col

# netstat -tunape
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address               Foreign Address             State       User       Inode      PID/Program name
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      0          15634      2616/sshd
tcp        0      0 127.0.0.1:25                0.0.0.0:*                   LISTEN      0          15855      2693/master
tcp        0     64 192.168.31.101:22           192.168.31.103:9670         ESTABLISHED 0          16306      2855/sshd
tcp        0      0 :::22                       :::*                        LISTEN      0          15636      2616/sshd
tcp        0      0 ::1:25                      :::*                        LISTEN      0          15857      2693/master
udp        0      0 0.0.0.0:68                  0.0.0.0:*                               0          15069      2436/dhclient
udp        0      0 0.0.0.0:68                  0.0.0.0:*                               0          14309      2248/dhclient
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# ss -tunap | col
Netid  State      Recv-Q Send-Q     Local Address:Port       Peer Address:Port
udp    UNCONN     0      0                      *:68                    *:*      users:(("dhclient",2436,5))
udp    UNCONN     0      0                      *:68                    *:*      users:(("dhclient",2248,5))
tcp    LISTEN     0      128                   :::22                   :::*      users:(("sshd",2616,4))
tcp    LISTEN     0      128                    *:22                    *:*      users:(("sshd",2616,3))
tcp    LISTEN     0      100                  ::1:25                   :::*      users:(("master",2693,13))
tcp    LISTEN     0      100            127.0.0.1:25                    *:*      users:(("master",2693,12))
tcp    ESTAB      0      64        192.168.31.101:22       192.168.31.103:9670   users:(("sshd",2855,3))
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最佳命令组合：nl -w1 -s' '

free | nl -w1 -s' '
1              total       used       free     shared    buffers     cached
2 Mem:        228716     198860      29856        160      28488      45132
3 -/+ buffers/cache:     125240     103476
4 Swap:      2031612         56    2031556
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time测量程序运行的时长

# time sleep 5
real    0m5.002s
user    0m0.000s
sys     0m0.001s
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