Linux学习笔记（第二课）
系统状态命令
ifconfig 查看网卡信息
ip addr 查看网卡信息
[root@localhost ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: ens160: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP group default qlen 1000
link/ether 00:0c:29:20:c4:5b brd ff:ff:ff:ff:ff:ff
inet 192.168.242.99/24 brd 192.168.242.255 scope global noprefixroute ens160
valid_lft forever preferred_lft forever
inet6 fe80::3f6b:e3e9:a7d9:79f/64 scope link noprefixroute
valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
link/ether 52:54:00:4d:b3:ed brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc fq_codel master virbr0 state DOWN group default qlen 1000
link/ether 52:54:00:4d:b3:ed brd ff:ff:ff:ff:ff:ff
[root@localhost ~]# ifconfig
ens160: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.242.99 netmask 255.255.255.0 broadcast 192.168.242.255
inet6 fe80::3f6b:e3e9:a7d9:79f prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:20:c4:5b txqueuelen 1000 (Ethernet)
RX packets 460 bytes 38766 (37.8 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 383 bytes 40531 (39.5 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1000 (Local Loopback)
RX packets 8 bytes 628 (628.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 8 bytes 628 (628.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255
ether 52:54:00:4d:b3:ed txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
uname 查看系统内核版本信息
[root@localhost ~]# uname
Linux
[root@localhost ~]# uname -a
Linux localhost.localdomain 4.18.0-80.el8.x86_64 #1 SMP Wed Mar 13 12:02:46 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
[root@localhost ~]# cat /etc/redhat-release
Red Hat Enterprise Linux release 8.0 (Ootpa)
[root@localhost ~]#
uptime 查看系统负载信息
[root@localhost ~]# uptime
09:07:34 up 47 min, 1 user, load average: 0.00, 0.00, 0.00
free 查看内存使用信息
[root@localhost ~]# free
total used free shared buff/cache available
Mem: 1849464 700212 684684 9616 464568 977980
Swap: 2097148 0 2097148
[root@localhost ~]# free -h
total used free shared buff/cache available
Mem: 1.8Gi 684Mi 668Mi 9.0Mi 453Mi 954Mi
Swap: 2.0Gi 0B 2.0Gi
[root@localhost ~]#
who 查看当前登入信息
[root@localhost ~]# who
root pts/0 2021-04-07 17:03 (192.168.242.1)
last 查看主机访问记录
[root@localhost ~]# last
root pts/0 192.168.242.1 Wed Apr 7 17:03 still logged in
reboot system boot 4.18.0-80.el8.x8 Wed Apr 7 17:00 still running
root pts/0 192.168.242.1 Wed Apr 7 08:21 - 10:35 (02:14)
reboot system boot 4.18.0-80.el8.x8 Wed Apr 7 08:19 still running
ping 测试网络的连通性 shell脚本时需设置ping次数 ping -c 4 192.168.1.10
tracepath 路由跟踪
netstat 显示网络连接、路由表、接口状态等信息
history 查看执行过的历史命令 （！id 执行当条id命令）
[root@localhost ~]# history
1 nmtui
2 systemctl resrart network
3 ifup
4 ip addr
5 reboot
6 ls
7 ll
8 q
9 quit
10 exit
[root@localhost ~]# !6
ls
anaconda-ks.cfg Documents initial-setup-ks.cfg Pictures Templates
Desktop Downloads Music Public Videos
[root@localhost ~]#
sosreport 收集系统配置及架构信息
2.5 查找定位文件命令
pwd 显示当前用户所处工作目录
[root@localhost network-scripts]# pwd
/etc/sysconfig/network-scripts
cd 切换工作目录
cd ~ 回到家目录
cd .. 返回上一层
cd - 返回上一次目录
ls 显示当前目录文件信息
[root@localhost ~]# ls -al
total 56
dr-xr-x---. 15 root root 4096 Apr 7 17:03 .
dr-xr-xr-x. 17 root root 224 Apr 6 15:21 ..
-rw-------. 1 root root 1848 Apr 6 15:43 anaconda-ks.cfg
-rw-------. 1 root root 650 Apr 7 10:35 .bash_history
-rw-r--r--. 1 root root 18 Aug 12 2018 .bash_logout
-rw-r--r--. 1 root root 176 Aug 12 2018 .bash_profile
-rw-r--r--. 1 root root 176 Aug 12 2018 .bashrc
drwx------. 11 root root 242 Apr 7 17:08 .cache
drwx------. 12 root root 227 Apr 7 17:08 .config
-rw-r--r--. 1 root root 100 Aug 12 2018 .cshrc
drwx------. 3 root root 25 Apr 6 15:47 .dbus
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Desktop
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Documents
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Downloads
-rw-------. 1 root root 16 Apr 6 15:50 .esd_auth
-rw-------. 1 root root 628 Apr 6 15:56 .ICEauthority
-rw-r--r--. 1 root root 2003 Apr 6 15:49 initial-setup-ks.cfg
-rw-------. 1 root root 35 Apr 6 16:30 .lesshst
drwx------. 3 root root 19 Apr 6 15:50 .local
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Music
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Pictures
drwxr-----. 3 root root 19 Apr 6 15:50 .pki
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Public
-rw-r--r--. 1 root root 129 Aug 12 2018 .tcshrc
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Templates
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Videos
-rw-------. 1 root root 870 Apr 6 16:25 .viminfo
-rw-------. 1 root root 67 Apr 7 17:03 .Xauthority
[root@localhost ~]# ll
total 8
-rw-------. 1 root root 1848 Apr 6 15:43 anaconda-ks.cfg
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Desktop
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Documents
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Downloads
-rw-r--r--. 1 root root 2003 Apr 6 15:49 initial-setup-ks.cfg
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Music
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Pictures
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Public
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Templates
drwxr-xr-x. 2 root root 6 Apr 6 15:50 Videos
tree 已树形图的形式列出目录内容及结构
[root@localhost ~]# ls
anaconda-ks.cfg Documents initial-setup-ks.cfg Pictures Templates
Desktop Downloads Music Public Videos
[root@localhost ~]# tree
.
├── anaconda-ks.cfg
├── Desktop
├── Documents
├── Downloads
├── initial-setup-ks.cfg
├── Music
├── Pictures
├── Public
├── Templates
└── Videos
find 按照指定条件查找对应的位置
[root@localhost ~]# find /etc -name "host*" -print
/etc/opa/hosts
/etc/host.conf
/etc/hosts
/etc/hosts.allow
/etc/hosts.deny
/etc/avahi/hosts
/etc/hostname
[root@localhost ~]#
locate按照名称快速搜索文件所对应的位置
whereis 找出命令文件目录及相关信息
which按照指定名称快速搜索二进制程序（命令）所对应的位置
2.6文本文件编辑命令
cat查看纯文本文件（内容较少的） 一把全显示
more用于查看纯文本文件（内容较多的） 看完即退出(百分比)
less用于查看纯文本文件（内容较多的） 可以向下向上翻页
--------------------
在命令模式下：
:set nu 显示行号
--------------------
head用于查看纯文本文件的前N行
[root@localhost ~]# head -n 5 /etc/sysconfig/network-scripts/ifcfg-ens160
TYPE=Ethernet
PROXY_METHOD=none
BROWSER_ONLY=no
BOOTPROTO=none
DEFROUTE=no
[root@localhost ~]#
tail查看纯文本文件的后N行或持续刷新文件的最新内容
[root@localhost ~]# tail -n 5 /etc/sysconfig/network-scripts/ifcfg-ens160
IPADDR=192.168.242.99
PREFIX=24
DNS1=114.114.114.114
PEERDNS=no
PEERROUTES=no
[root@localhost ~]#
tr命令用于替换文本内容中的字符，translate
[root@linuxprobe ~]# cat anaconda-ks.cfg | tr [a-z] [A-Z]
wc命令用于统计指定文本文件的行数、字数或字节数，全称为：“word counts”
[root@localhost ~]# wc -l /etc/sysconfig/network-scripts/ifcfg-ens160
20 /etc/sysconfig/network-scripts/ifcfg-ens160
[root@localhost ~]# wc -c /etc/sysconfig/network-scripts/ifcfg-ens160
360 /etc/sysconfig/network-scripts/ifcfg-ens160
stat命令用于查看文件的具体存储细节和时间等信息，全称为：“status”
[root@localhost ~]# stat /etc/sysconfig/network-scripts/ifcfg-ens160
File: /etc/sysconfig/network-scripts/ifcfg-ens160
Size: 360 Blocks: 8 IO Block: 4096 regular file
Device: fd00h/64768d Inode: 34300988 Links: 1
Access: (0644/-rw-r--r--) Uid: ( 0/ root) Gid: ( 0/ root)
Context: system_u:object_r:net_conf_t:s0
Access: 2021-04-07 17:00:53.156655292 -0400
Modify: 2021-04-06 16:02:14.554153754 -0400
Change: 2021-04-06 16:02:14.555153754 -0400
Birth: -
[root@localhost ~]#
grep命令用于按行提取文本内容
cut命令用于按列提取文本内容
diff命令用于比较多个文件之间内容的差异，全称为：“different”
uniq命令用于去除文本中连续的重复行，全称为：“unique”
sort命令用于对文本内容进行再排序
