Shulou(Shulou.com)06/01 Report--

1. Ifconfig command

Ifconfig is a command used to display or configure network devices (network interface cards) in linux. The English full name is network interfaces configuring.

1. Ifconfig-a

[root@test1 yum.repos.d] # ifconfig-a

Eth0 Link encap:Ethernet HWaddr 00:0C:29:1F:06:D4

Inet addr:192.168.1.108 Bcast:192.168.1.255 Mask:255.255.255.0

Inet6 addr: fe80::20c:29ff:fe1f:6d4/64 Scope:Link

UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1

RX packets:227870 errors:0 dropped:0 overruns:0 frame:0

TX packets:22314 errors:0 dropped:0 overruns:0 carrier:0

Collisions:0 txqueuelen:1000

RX bytes:29699855 (28.3 MiB) TX bytes:5637694 (5.3 MiB)

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:65536 Metric:1

RX packets:184 errors:0 dropped:0 overruns:0 frame:0

TX packets:184 errors:0 dropped:0 overruns:0 carrier:0

Collisions:0 txqueuelen:0

RX bytes:12878 (12.5 KiB) TX bytes:12878 (12.5 KiB)

[root@test1 yum.repos.d] #

Through this command, you can see the ip address and mac address of the network card, as well as the lo loopback address.

First line: connection type: Ethernet (Ethernet) HWaddr (hardware mac address)

Second line: IP address, subnet, mask of the network card

Line 3: UP (for network card on status) RUNNING (network cable for network card is connected) MULTICAST (support for multicast) MTU:1500 (maximum transmission unit): 1500 bytes

Fourth and fifth elements: statistics of receiving and sending packets

Line 7: receive and send data byte statistics.

2. Ifconfig interface [up | down] / / start or disable the interface

3. Ifconfig interface IP/mask / / set the ip address for the interface

4. Ifconfig interface-alias IP/mask / / set the ip address for the interface alias; effective immediately

II. Route

View: route-n

Add: route add

Route add [- net |-host] target [netmask Nm] [gw Gw] [[dev] If]

Destination: 192.168.1.3 Gateway: 172.16.0.1

~] # route add-host 192.168.1.3 gw 172.16.0.1 dev eth0

Destination: 192.168.0.0 Gateway: 172.16.0.1

~] # route add-net 192.168.0.0 netmask 255.255.255.0 gw 172.16.0.1 dev eth0

~] # route add-net 192.168.0.0 gw 24 gw 172.16.0.1 dev eth0

Default route, gateway: 172.16.0.1

~] # route add-net 0.0.0.0 netmask 0.0.0.0 gw 172.16.0.1

~] # route add default gw 172.16.0.1

Delete: route del

Route del [- net |-host] target [gw Gw] [netmask Nm] [[dev] If]

Destination: 192.168.1.3 Gateway: 172.16.0.1

~] # route del-host 192.168.1.3

Destination: 192.168.0.0 Gateway: 172.16.0.1

~] # route del-net 192.168.0.0 netmask 255.255.255.0

III. Netstat

Netstat-Print network connections, routing tables, interface statistics, masquerade connections, and multicast memberships

Show network connections:

Netstat [--tcp |-t] [--udp |-- raw |-w] [--listening |-l] [--all |-a] [--numeric |-n] [--extend |-e [--extend |-e]] [--program |-p]

-t: related to tcp protocol

-u: related to udp protocol

-w: raw socket related

-l: in monitoring state

-a: all statu

-n: display IP and port in numbers

-e: extended format

-p: displays related processes and PID

Common combinations:

-tan.-uan.-tnl.-unl.

Display the routing table:

Netstat {--route |-r} [--numeric |-n]

-r: displays the kernel routing table

-n: numeric format

Display interface statistics:

Netstat {--interfaces |-I |-I} [iface] [--all |-a] [--extend |-e] [--program |-p] [--numeric |-n]

# netstat-I

# netstat-I IFACE

IV. Ip

Linux's ip command is similar to ifconfig, but the former is more powerful and is designed to replace the latter

Ip-show / manipulate routing, devices, policy routing and tunnels

Ip [OPTIONS] OBJECT {COMMAND | help}

OBJECT: = {link | addr | route}

Link OBJECT:

Ip link-network device configuration

Set

Dev IFACE

Properties can be set:

Up and down: activates or disables the specified interface

Show

[dev IFACE]: specify the interface

[up]: only interfaces that are active are displayed

Ip address-protocol address management

Ip addr {add | del} IFADDR dev STRING

[label LABEL]: indicates the alias of the network card when adding an address

[scope {global | link | host}]: indicates the scope

Global: globally available

Link: only links are available

Host: available locally

[broadcast ADDRESS]: indicates the broadcast address

Ip address show-look at protocol addresses

[dev DEVICE]

[label PATTERN]

[primary and secondary]

Ip address flush-flush protocol addresses

Use the same format as show

Ip route-routing table management

Ip route add

Add Route: ip route add TARGET via GW dev IFACE src SOURCE_IP

TARGET:

Host routing: IP

Network routing: NETWORK/MASK

Add Gateway: ip route add defalt via GW dev IFACE

Ip route delete

Delete route: ip route del TARGET

Ip route show

Ip route flush

[dev IFACE]

[via PREFIX]

5. Ss

Ss is the abbreviation of Socket Statistics. As the name implies, the ss command can be used to get socket statistics, which can display something similar to netstat. But the advantage of ss is that it can display more and more detailed information about TCP and connection status, and is faster and more efficient than netstat.

Format: ss [OPTION]... [FILTER]

Options:

-t: related to tcp protocol

-u: related to udp protocol

-w: bare socket related

-x:unix sock related

-l: connection with listen statu

-a: all

-n: numeric format

-p: related programs and PID

-e: extended information

-m: memory usage

-o: timer information

The running result is clear at a glance, and the speed is very fast.

[root@test1 yum.repos.d] # ss-tanlp

State Recv-Q Send-Q Local Address:Port Peer Address:Port

LISTEN 0 128: 22: * users: ("sshd", 1813pr. 4)

LISTEN 0 128 *: 22 *: * users: ("sshd", 1813 jade 3)

LISTEN 0 128: 40470: * users: ("rpc.statd", 1635. 11)

LISTEN 0 128 127.0.0.1 LISTEN 631 *: * users: ("cupsd", 1673 Magne7))

LISTEN 0 128:: 1 LISTEN 631: * users: ("cupsd", 1673 Magne6))

LISTEN 0 100:: 1:25: * users: ("master", 1990, 13)

LISTEN 0 100 127.0.0.1 LISTEN 25 *: * users: ("master", 1990 Magi 12))

LISTEN 0 128: 58524: * users: ("rpc.mountd", 3684. 14)

LISTEN 0 64:: 2049: *

LISTEN 0 64 *: 2049 *: *

LISTEN 0 128: 45697: * users: ("rpc.mountd", 3684 users 18)

LISTEN 0 64 *: 42242 *: *

LISTEN 0 128 *: 44843 *: * users: ("rpc.mountd", 368 4pr 16)

LISTEN 0128 *: 875 *: * users: ("rpc.rquotad", 3679pr. 4)

LISTEN 0 128 *: 55244 *: * users: ("rpc.mountd", 368 4pr 8)

LISTEN 0 64:: 59629: *

LISTEN 0128 *: 33549 *: * users: (("rpc.mountd", 3684, 12))

LISTEN 0128 *: 53679 *: * users: ("rpc.statd", 1635pr. 9)

LISTEN 0 128: 111: * users: (("rpcbind", 1517))

LISTEN 0128 *: 111l *: * users: ("rpcbind", 1517pr 8)

LISTEN 0 128: 42480: * users: (("rpc.mountd", 3684, 10))

[root@test1 yum.repos.d] #

VI. Nmcli

Nmcli [OPTIONS] OBJECT {COMMAND | help}

Device-show and manage network interfaces

Connection-start, stop, and manage network connections

How to modify attributes such as IP address:

# nmcli connection modify IFACE [+ | -] setting.property value

Setting.property:

Ipv4.addresses

Ipv4.gateway

Ipv4.dns1

Ipv4.method

Manual

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