51. Linux Shell Command, route, ifconfig

3. Route

1) route [-nee]

ROute add [-net |-host] [domain or host] netmask [mask] [GW | Dev]

Route del [-net |-host] [domain or host] netmask[Mask] [GW | Dev]

2) Option

①-N: not usedProtocolOr host name, directly using IP or port number;

②-Ee: use more detailed information to display

Add and delete (DEL) Route parameters:

①-Net: indicates that the followed route is a domain;

②-Host: The route connecting to a single host;

③Netmask:Subnet Mask;

④GW: Short for gateway;

⑤DeVSpecify the network card to connect, followed by eth0, etc.

For the description of flags in the result, see [1 ].

3) Example

1) Route del-net 169.254.0.0 netmask 255.255.0.0 Dev eth0 // you must write all the items in the route table.

2) Route add-net 192.168.100.0 netmask 255.255.255.0 Dev eth0

3) Route add default GW 192.168.1.250

/Etc/init. d/network restart // all the preceding settings are invalid. The ifcfg-ethx settings are the main ones.

Default = 0.0.0.0/0.0.0.0

4. ifconfig, IFUP, and ifdown

1) Description

⑥Ifconfig {interface} {up | down}

7.Ifconfig interface address {options}

You can set a virtual network interface to specify multiple IP addresses for a network interface. The virtual interface is eth0: 0, eth0: 1, eth0: 2 ..... eth1n. For example, we can use different IP addresses to run multiple HTTPd servers.

2) Option

Interface: network card number, including eth0, eth1, ppp0, etc.

Options ::

①Up, down: Start (up) or close (down) the network interface (no parameters are involved)

②MTU: Different MTU values can be set, for example, MTU 1500 (unit: byte)

③Netmask: ChildNetmask;

④Broadcast: broadcast address

3) Example

Ifconfig eth0 192.168.100.100 // set the IP address of eth0

Ifconfig eth0 192.168.100.100 netmask implements 255.255.128 MTU 8000

Ifconfig eth0: 0 192.168.50.50 // ETH0: 0. On this physical Nic, simulate another network.AddressThat is, multiple IP addresses are set on a network card.

Ifconfig eth0: 0 down

/Etc/init. d/network restart//Just nowOfIf all settings are invalid, the ifcfg-ethx settings are used as the master.

/Etc/sysconfig/Network/config

Ifconfig eth1: 0 192.168.1.250 HW ether 00: 11: 00: 00: 11: 44 netmask 255.255.255.0 broadcast 192.168.1.255 up/HW follows the network interface type, ether indicates Ethernet

4) IFUP, ifdown is two feetIn the/etc/sysconfig/network-scripts directory., And start and close with the corresponding script.

IFUP | ifdown {interface}

5. ip command [1]

Reference

[1] Explain the commands

Http://linux.vbird.org/linux_server/0140networkcommand.php#netstat

[2] better explanation of TCP State, such as time_wait: the socket is waiting after close to handle packets still in the network.

Http://linux.die.net/man/8/netstat

[3]Http://www.linuxso.com/command/netstat.html

[4] traceroute usage example

Http://blog.sina.com.cn/s/blog_4895289e010009bn.html

Nice to talk about the ins and outs

Http://blog.chinaunix.net/space.php? Uid = 20172731 & Do = Blog & cuid = 159630

[5] ifconfig usage

Http://www.cublog.cn/u2/78880/showart_1879201.html