Linux系统专家必学的20个命令

时间:2020-11-11 15:50:56 Linux认证 我要投稿

Linux系统专家必学的20个命令

  Linux系统专家必学的命令有哪些?Linux系统有哪些命令非常有用呢?下面跟yjbys小编一起来看看吧!

  1. 命令: ifconfig

  ifconfig用来配置常驻内核的网络接口信息。在系统启动必要时用来设置网络适配器的信息。之后,它通常是只需要在调试时或当系统需要调整时使用。

  检查活动网络适配器

  [avishek@tecmint ~]$ ifconfig

  eth0 Link encap:Ethernet HWaddr 40:2C:F4:EA:CF:0E

  inet addr:192.168.1.3 Bcast:192.168.1.255 Mask:255.255.255.0

  inet6 addr: fe80::422c:f4ff:feea:cf0e/64 Scope:Link

  UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

  RX packets:163843 errors:0 dropped:0 overruns:0 frame:0

  TX packets:124990 errors:0 dropped:0 overruns:0 carrier:0

  collisions:0 txqueuelen:1000

  RX bytes:154389832 (147.2 MiB) TX bytes:65085817 (62.0 MiB)

  Interrupt:20 Memory:f7100000-f7120000

  lo Link encap:Local Loopback

  inet addr:127.0.0.1 Mask:255.0.0.0

  inet6 addr: ::1/128 Scope:Host

  UP LOOPBACK RUNNING MTU:16436 Metric:1

  RX packets:78 errors:0 dropped:0 overruns:0 frame:0

  TX packets:78 errors:0 dropped:0 overruns:0 carrier:0

  collisions:0 txqueuelen:0

  RX bytes:4186 (4.0 KiB) TX bytes:4186 (4.0 KiB)

  检查所有的网络适配器

  “-a”参数用来显示所有网络适配器(网卡)的详细信息,包括那些停用的适配器。

  [avishek@tecmint ~]$ ifconfig -a

  eth0 Link encap:Ethernet HWaddr 40:2C:F4:EA:CF:0E

  inet addr:192.168.1.3 Bcast:192.168.1.255 Mask:255.255.255.0

  inet6 addr: fe80::422c:f4ff:feea:cf0e/64 Scope:Link

  UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

  RX packets:163843 errors:0 dropped:0 overruns:0 frame:0

  TX packets:124990 errors:0 dropped:0 overruns:0 carrier:0

  collisions:0 txqueuelen:1000

  RX bytes:154389832 (147.2 MiB) TX bytes:65085817 (62.0 MiB)

  Interrupt:20 Memory:f7100000-f7120000

  lo Link encap:Local Loopback

  inet addr:127.0.0.1 Mask:255.0.0.0

  inet6 addr: ::1/128 Scope:Host

  UP LOOPBACK RUNNING MTU:16436 Metric:1

  RX packets:78 errors:0 dropped:0 overruns:0 frame:0

  TX packets:78 errors:0 dropped:0 overruns:0 carrier:0

  collisions:0 txqueuelen:0

  RX bytes:4186 (4.0 KiB) TX bytes:4186 (4.0 KiB)

  virbr0 Link encap:Ethernet HWaddr 0e:30:a3:3a:bf:03

  inet addr:192.168.122.1 Bcast:192.168.122.255 Mask:255.255.255.0

  UP BROADCAST MULTICAST MTU:1500 Metric:1

  RX packets:0 errors:0 dropped:0 overruns:0 frame:0

  TX packets:0 errors:0 dropped:0 overruns:0 carrier:0

  collisions:0 txqueuelen:0

  RX bytes:0 (0.0 B) TX bytes:0 (0.0 B)

  停用网络适配器

  [avishek@tecmint ~]$ ifconfig eth0 down

  启用网络适配器

  [avishek@tecmint ~]$ ifconfig eth0 up

  指定IP地址到网络适配器

  为网络适配器eth0设定IP地址“192.168.1.12”.

  [avishek@tecmint ~]$ ifconfig eth0 192.168.1.12

  更改网络适配器eth0的子网掩码

  [avishek@tecmint ~]$ ifconfig eth0 netmask 255.255.255.

  更改网络适配器eth0的广播地址

  [avishek@tecmint ~]$ ifconfig eth0 broadcast 192.168.1.255

  为网络适配器eth0指定IP地址,子网掩码,广播地址

  [avishek@tecmint ~]$ ifconfig eth0 192.168.1.12 netmask 255.255.255.0 broadcast 192.168.1.255

  注Note:如果你设置一块无线网卡的信息,你可以使用的命令是“iwconfig”.欲知更多ifconfig命令的例子和使用方法,读“15个有用的ifconfig 命令”.

  2. 命令: netstat

  netstat命令显示各种网络相关的信息,如网络连接,路由表,接口统计,伪装连接,组播成员身份等….

  列出所有的网络端口

  [avishek@tecmint ~]$ netstat -a

  Active UNIX domain sockets (servers and established)

  Proto RefCnt Flags Type State I-Node Path

  unix 2 [ ACC ] STREAM LISTENING 741379 /run/user/user1/keyring-I5cn1c/gpg

  unix 2 [ ACC ] STREAM LISTENING 8965 /var/run/acpid.socket

  unix 2 [ ACC ] STREAM LISTENING 18584 /tmp/.X11-unix/X0

  unix 2 [ ACC ] STREAM LISTENING 741385 /run/user/user1/keyring-I5cn1c/ssh

  unix 2 [ ACC ] STREAM LISTENING 741387 /run/user/user1/keyring-I5cn1c/pkcs11

  unix 2 [ ACC ] STREAM LISTENING 20242 @/tmp/dbus-ghtTjuPN46

  ....

  显示所有tcp相关端口

  [avishek@tecmint ~]$ netstat -at

  Active Internet connections (servers and established)

  Proto Recv-Q Send-Q Local Address Foreign Address State

  tcp 0 0 localhost:mysql *:* LISTEN

  tcp 0 0 *:5901 *:* LISTEN

  tcp 0 0 *:5902 *:* LISTEN

  tcp 0 0 *:x11-1 *:* LISTEN

  tcp 0 0 *:x11-2 *:* LISTEN

  tcp 0 0 *:5938 *:* LISTEN

  tcp 0 0 localhost:5940 *:* LISTEN

  ...

  显示所有连接的统计信息

  [avishek@tecmint ~]$ netstat -s

  Ip:

  994239 total packets received

  0 forwarded

  0 incoming packets discarded

  165741 incoming packets delivered

  3248924 requests sent out

  8 outgoing packets dropped

  Icmp:

  29460 ICMP messages received

  166 input ICMP message failed.

  ICMP input histogram:

  destination unreachable: 98

  redirects: 29362

  2918 ICMP messages sent

  0 ICMP messages failed

  ICMP output histogram:

  destination unreachable: 2918

  IcmpMsg:

  InType3: 98

  InType5: 29362

  OutType3: 2918

  Tcp:

  94533 active connections openings

  23 passive connection openings

  1870 failed connection attempts

  7194 connection resets received

  ....

  好的!由于某些原因如果你不想解析netstat 输出的主机、端口和用户名称的`话 。

  [avishek@tecmint ~]$ netstat -an

  好,你可能需要获取的 netstat 持续输出的动态信息,通过传递中断输出指令 (ctrl + c)来停止。

  [avishek@tecmint ~]$ netstat -c

  更多关于“netstat”的例子和使用方法,浏览文章“20个netstat 的使用案例”。

  3. 命令: nslookup

  网络实用程序,用于获得互联网服务器的信息。顾名思义,该实用程序将发现通过查询 DNS 域的名称服务器信息。

  [avishek@tecmint ~]$ nslookup tecmint.com

  Server: 192.168.1.1

  Address: 192.168.1.1

  #53

  Non-authoritative answer:

  Name: tecmint.com

  Address: 50.16.67.239

  查询邮件交换器记录

  [avishek@tecmint ~]$ nslookup -query=mx tecmint.com

  Server: 192.168.1.1

  Address: 192.168.1.1

  #53

  Non-authoritative answer:

  tecmint.com mail exchanger = 0 smtp.secureserver.net.

  tecmint.com mail exchanger = 10 mailstore1.secureserver.net.

  Authoritative answers can be found from:

  查询域名服务器

  [avishek@tecmint ~]$ nslookup -type=ns tecmint.com

  Server: 192.168.1.1

  Address: 192.168.1.1

  #53

  Non-authoritative answer:

  tecmint.com nameserver = ns3404.com.

  tecmint.com nameserver = ns3403.com.

  Authoritative answers can be found from:

  查询DNS记录

  [avishek@tecmint ~]$ nslookup -type=any tecmint.com

  Server: 192.168.1.1

  Address: 192.168.1.1

  #53

  Non-authoritative answer:

  tecmint.com mail exchanger = 10 mailstore1.secureserver.net.

  tecmint.com mail exchanger = 0 smtp.secureserver.net.

  tecmint.com nameserver = ns06.domaincontrol.com.

  tecmint.com nameserver = ns3404.com.

  tecmint.com nameserver = ns3403.com.

  tecmint.com nameserver = ns05.domaincontrol.com.

  Authoritative answers can be found from:

  查询起始授权机构

  [avishek@tecmint ~]$ nslookup -type=soa tecmint.com

  Server: 192.168.1.1

  Address: 192.168.1.1

  #53

  Non-authoritative answer:

  tecmint.com

  origin = ns3403.hostgator.com

  mail addr = dnsadmin.gator1702.hostgator.com

  serial = 2012081102

  refresh = 86400

  retry = 7200

  expire = 3600000

  minimum = 86400

  Authoritative answers can be found from:

  查询端口号

  更改使用你想要连接的端口号

  [avishek@tecmint ~]$ nslookup -port 56 tecmint.com

  Server: tecmint.com

  Address: 50.16.76.239

  #53

  Name: 56

  Address: 14.13.253.12

  4. 命令: dig

  dig是查询DNS 域名服务器的工具,可以查询的主机地址、 邮件交流、 域名服务器相关的信息。在任何 Linux (Unix) 或 Macintosh OS X 操作系统上,都可以使用该工具。dig的最典型的用法是单个主机的查询。

  [avishek@tecmint ~]$ dig tecmint.com

  ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6 <<>> tecmint.com

  ;; global options: +cmd

  ;; Got answer:

  ;; ->>HEADER<

  关闭注释行

  [avishek@tecmint ~]$ dig tecmint.com +nocomments

  ; <<>> DiG 9.8.2rc1-RedHat-9.8.2-0.17.rc1.el6 <<>> tecmint.com +nocomments