修改主机名

# 方式一：
[root@local-work ~]# hostnamectl set-hostname local-work
# 需要重新登录或者执行一个解析器

# 方式二：
[root@local-work ~]# echo "string" > /etc/hostname 
[root@local-work ~]# cat /etc/hostname
string
# 直接修改文件，不会立即生效，需要重启。

查看系统IP

# 方式一：
[root@string ~]# ip a
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:0c:29:20:7e:96 brd ff:ff:ff:ff:ff:ff
    inet 192.168.15.100/24 brd 192.168.15.255 scope global noprefixroute eth0
       valid_lft forever preferred_lft forever
    inet6 fe80::962c:f186:8d31:5eec/64 scope link noprefixroute 
       valid_lft forever preferred_lft forever

# 方式二：
[root@string ~]# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.15.100  netmask 255.255.255.0  broadcast 192.168.15.255
        inet6 fe80::962c:f186:8d31:5eec  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:20:7e:96  txqueuelen 1000  (Ethernet)
        RX packets 119  bytes 11208 (10.9 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 102  bytes 14496 (14.1 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

# 查看某一个网卡的信息
[root@string ~]# ifconfig eth0
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500
        inet 192.168.15.100  netmask 255.255.255.0  broadcast 192.168.15.255
        inet6 fe80::962c:f186:8d31:5eec  prefixlen 64  scopeid 0x20<link>
        ether 00:0c:29:20:7e:96  txqueuelen 1000  (Ethernet)
        RX packets 119  bytes 11208 (10.9 KiB)
        RX errors 0  dropped 0  overruns 0  frame 0
        TX packets 102  bytes 14496 (14.1 KiB)
        TX errors 0  dropped 0 overruns 0  carrier 0  collisions 0

系统时间

[root@string ~]# date
Fri Mar  5 09:50:27 CST 2021
[root@string ~]# date +%Y-%m-%d
2021-03-05

# 格式化时间
[root@string ~]# # 09:58:30
[root@string ~]# date +%H:%M:%S
10:01:44
[root@string ~]# date +%Y-%m-%d_%H:%M:%S
2021-03-05_10:02:05

# 设置时间
[root@string ~]# date -s "2029-03-05 10:02:44"
Mon Mar  5 10:02:44 CST 2029
[root@string ~]# date +%Y-%m-%d_%H:%M:%S
2029-03-05_10:03:03

# 同步互联网时间
[root@string ~]# yum install -y ntpdate
[root@string ~]# ntpdate ntp.aliyun.com

# 系统硬件时钟
[root@string ~]# hwclock -r
Fri 05 Mar 2021 10:10:40 AM CST  -0.271305 seconds

# 系统软件时钟
[root@string ~]# date
Mon Mar  5 10:03:30 CST 2029

# 获取硬件时间
[root@string ~]# hwclock -r
Fri 05 Mar 2021 10:13:19 AM CST  -0.473926 seconds

# 将硬件时间同步到系统时间
[root@string ~]# hwclock -r
Fri 05 Mar 2021 10:13:19 AM CST  -0.473926 seconds
[root@string ~]# date
Mon Mar  5 10:06:20 CST 2029
[root@string ~]# hwclock -s
[root@string ~]# date
Fri Mar  5 10:14:19 CST 2021

# 查看时区状态
[root@string ~]# timedatectl status
      Local time: Fri 2021-03-05 10:26:39 CST
  Universal time: Fri 2021-03-05 02:26:39 UTC
        RTC time: Fri 2021-03-05 02:26:33
       Time zone: Asia/Shanghai (CST, +0800)
     NTP enabled: n/a
NTP synchronized: no
 RTC in local TZ: no
      DST active: n/a

# 设置时区
[root@string ~]# timedatectl set-timezone Asia/Shanghai

重启和关机机器

[root@string ~]# reboot 
[root@string ~]# init 6
[root@string ~]# shutdown -r 0
[root@string ~]# halt 

# 重启
reboot

# 关机
shutdown -h 0