Linux系統專家必學的20個命令

Linux系統專家必學的命令有哪些?Linux系統有哪些命令非常有用呢?下面跟yjbys小編一起來看看吧!

　　1. 命令: ifconfig

ifconfig用來配置常駐內核的網絡接口信息。在系統啟動必要時用來設置網絡適配器的信息。之後，它通常是隻需要在調試時或當系統需要調整時使用。

檢查活動網絡適配器

[avishek@tecmint ~]$ ifconfig

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

inet addr: Bcast: Mask:

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: Mask:

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)

檢查所有的網絡適配器

“-a”參數用來顯示所有網絡適配器(網卡)的詳細信息,包括那些停用的適配器。

[avishek@tecmint ~]$ ifconfig -a

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

inet addr: Bcast: Mask:

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: Mask:

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: Bcast: Mask:

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)

停用網絡適配器

[avishek@tecmint ~]$ ifconfig eth0 down

啟用網絡適配器

[avishek@tecmint ~]$ ifconfig eth0 up

指定IP地址到網絡適配器

為網絡適配器eth0設定IP地址“”.

[avishek@tecmint ~]$ ifconfig eth0

更改網絡適配器eth0的子網掩碼

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

更改網絡適配器eth0的廣播地址

[avishek@tecmint ~]$ ifconfig eth0 broadcast

為網絡適配器eth0指定IP地址,子網掩碼，廣播地址

[avishek@tecmint ~]$ ifconfig eth0 netmask broadcast

注Note:如果你設置一塊無線網卡的信息,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，讀“15個有用的ifconfig 命令”.

　　2. 命令: netstat

netstat命令顯示各種網絡相關的信息，如網絡連接,路由表,接口統計,偽裝連接,組播成員身份等….

列出所有的網絡端口

[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/et

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

....

顯示所有tcp相關端口

[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

...

顯示所有連接的統計信息

[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!由於某些原因如果你不想解析netstat 輸出的主機、端口和用户名稱的話 。

[avishek@tecmint ~]$ netstat -an

好，你可能需要獲取的 netstat 持續輸出的動態信息，通過傳遞中斷輸出指令 (ctrl + c)來停止。

[avishek@tecmint ~]$ netstat -c

更多關於“netstat”的例子和使用方法，瀏覽文章“20個netstat 的使用案例”。

　　3. 命令： nslookup

網絡實用程序，用於獲得互聯網服務器的信息。顧名思義，該實用程序將發現通過查詢 DNS 域的名稱服務器信息。

[avishek@tecmint ~]$ nslookup

Server:

Address:

#53

Non-authoritative answer:

Name:

Address:

查詢郵件交換器記錄

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

Server:

Address:

#53

Non-authoritative answer:

mail exchanger = 0 .

mail exchanger = 10 .

Authoritative answers can be found from:

查詢域名服務器

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

Server:

Address:

#53

Non-authoritative answer:

nameserver = .

nameserver = .

Authoritative answers can be found from:

查詢DNS記錄

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

Server:

Address:

#53

Non-authoritative answer:

mail exchanger = 10 .

mail exchanger = 0 .

nameserver = .

nameserver = .

nameserver = .

nameserver = .

Authoritative answers can be found from:

查詢起始授權機構

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

Server:

Address:

#53

Non-authoritative answer:

origin =

mail addr =

serial = 2012081102

refresh = 86400

retry = 7200

expire = 3600000

minimum = 86400

Authoritative answers can be found from:

查詢端口號

更改使用你想要連接的端口號

[avishek@tecmint ~]$ nslookup -port 56

Server:

Address:

#53

Name: 56

Address:

　　4. 命令: dig

dig是查詢DNS 域名服務器的工具，可以查詢的主機地址、 郵件交流、 域名服務器相關的信息。在任何 Linux (Unix) 或 Macintosh OS X 操作系統上，都可以使用該工具。dig的最典型的用法是單個主機的查詢。

[avishek@tecmint ~]$ dig

; <<>> DiG 6 <<>>

;; global options: +cmd

;; Got answer:

;; ->>HEADER<

關閉註釋行

[avishek@tecmint ~]$ dig +nocomments

; <<>> DiG 6 <<>> +nocomments