basic play

[root@wen ~]# w
 19:01:27 up 1 day,  7:06,  3 users,  load average: 0.00, 0.00, 0.00
USER     TTY      FROM              LOGIN@   IDLE   JCPU   PCPU WHAT
root     tty1     -                Sun06   36:30m  0.00s  0.00s -bash
root     pts/0    192.168.13.1     14:00    2:39m  0.45s  0.45s -bash
root     pts/1    192.168.13.1     19:01    0.00s  0.00s  0.00s w

[root@wen ~]# uptime
 19:01:38 up 1 day,  7:06,  3 users,  load average: 0.00, 0.00, 0.00

查看负载信息

查看ip
ifconfig
ip addr -----  man ip 查看更多

查看磁盘使用情况
[root@wen ~]# df -h
Filesystem      Size  Used Avail Use% Mounted on
/dev/sda2       8.6G  2.3G  5.9G  29% /
tmpfs           491M     0  491M   0% /dev/shm
/dev/sda1       190M   36M  145M  20% /boot

查看inode使用情况
[root@wen ~]# df -i
Filesystem     Inodes IUsed  IFree IUse% Mounted on
/dev/sda2      577088 81403 495685   15% /
tmpfs          125596     1 125595    1% /dev/shm
/dev/sda1       51200    38  51162    1% /boot

查看当前系统内存的使用情况

[root@wen ~]# free -m
             total       used       free     shared    buffers     cached
Mem:           981        232        748          0         69         62
-/+ buffers/cache:        100        880
Swap:         1023          0       1023

[root@wen ~]# netstat -lntpu|grep 22
tcp        0      0 0.0.0.0:22                  0.0.0.0:*                   LISTEN      1540/sshd
tcp        0      0 :::22                       :::*                        LISTEN      1540/sshd

[root@wen ~]# ss -tunlp|grep 22
tcp    LISTEN     0      128                   :::22                   :::*      users:(("sshd",1540,4))
tcp    LISTEN     0      128                    *:22                    *:*      users:(("sshd",1540,3))

[root@wen test]# lsof -i :22
COMMAND  PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
sshd    1540 root    3u  IPv4  11157      0t0  TCP *:ssh (LISTEN)
sshd    1540 root    4u  IPv6  11159      0t0  TCP *:ssh (LISTEN)
sshd    7296 root    3r  IPv4  24132      0t0  TCP bogon:ssh->bogon:64386 (ESTABLISHED)
sshd    8060 root    3r  IPv4  25604      0t0  TCP bogon:ssh->bogon:54262 (ESTABLISHED)
sshd    8167 root    3r  IPv4  26440      0t0  TCP bogon:ssh->bogon:54599 (ESTABLISHED)
[root@wen test]# lsof -i tcp:22
COMMAND  PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
sshd    1540 root    3u  IPv4  11157      0t0  TCP *:ssh (LISTEN)
sshd    1540 root    4u  IPv6  11159      0t0  TCP *:ssh (LISTEN)
sshd    7296 root    3r  IPv4  24132      0t0  TCP 192.168.13.128:ssh->bogon:64386 (ESTABLISHED)
sshd    8060 root    3r  IPv4  25604      0t0  TCP 192.168.13.128:ssh->bogon:54262 (ESTABLISHED)
sshd    8167 root    3r  IPv4  26440      0t0  TCP 192.168.13.128:ssh->bogon:54599 (ESTABLISHED)

查看80端口

查看文本

[root@wen ~]# sed -n '1,3p' /etc/passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin

[root@wen ~]# awk 'NR<4{print $0}' /etc/passwd
root:x:0:0:root:/root:/bin/bash
bin:x:1:1:bin:/bin:/sbin/nologin
daemon:x:2:2:daemon:/sbin:/sbin/nologin

将/home/tong/test目录下大于100k的文件移到/tmp目录
[root@wen ~]# cd /home/tong/test
[root@wen test]# dd if=/dev/zero of=oldboy bs=1K count=111
记录了111+0 的读入
记录了111+0 的写出
113664字节(114 kB)已复制，0.000403373 秒，282 MB/秒

[root@wen test]# ls
oldboy

[root@wen test]# find . -type f -size +100k|xargs -i mv {} /tmp/
[root@wen test]# ls /tmp/
ps - report a snapshot of the current processes.
[root@wen test]# ps aux|grep 8338
root       8363  0.0  0.0 103320   860 pts/1    S+   19:52   0:00 grep --color=auto 8338

网卡配置文件，最后的网卡序号可能会变

[root@wen test]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
TYPE=Ethernet
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=dhcp
USERCTL=no
IPV6INIT=no
HWADDR=00:0c:29:e9:95:dd
DNS2=8.8.8.8
DNS1=192.168.59.2
PEERDNS=yes

查看DNS，网卡也可以配置DNS（最先生效），最终也会解析下面的DNS文件
[root@wen test]# cat /etc/resolv.conf
; generated by /sbin/dhclient-script
search localdomain
nameserver 192.168.13.2

真正查看网卡
[root@wen test]# ethtool eth0
Settings for eth0:
Supported ports: [ TP ]
Supported link modes:   10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
                        1000baseT/Full

Supported pause frame use: No
Supports auto-negotiation: Yes
Advertised link modes:  10baseT/Half 10baseT/Full
                        100baseT/Half 100baseT/Full
                        1000baseT/Full

Advertised pause frame use: No
Advertised auto-negotiation: Yes
Speed: 1000Mb/s
Duplex: Full
Port: Twisted Pair
PHYAD: 0
Transceiver: internal
Auto-negotiation: on
MDI-X: off (auto)
Supports Wake-on: d
Wake-on: d
Current message level: 0x00000007 (7)
       drv probe link
Link detected: yes

查看二进制文件
[root@wen test]# od /bin/ls
统计/var/log/下的文件数
[root@wen test]# find /var/log -type f|wc -l
77
[root@wen test]# find /var/log -maxdepth 1 -type f|wc -l
42