Linux Network integrated Command--IP

IP is a powerful network configuration tool in the Iproute2 package, it can replace some traditional network management tools, such as ifconfig, route, etc., with the privilege of Superuser. This command is supported by almost all Linux distributions.

2. Format
IP [OPTIONS] OBJECT [COMMAND [ARGUMENTS]]

3. Main parameters
Options is the option to modify the IP behavior or change its output. All options start with a-character, and are divided into two forms: long and short. Currently, IP supports the options shown in table 1.

Object is the one to which the manager obtains information. The current IP-aware objects are shown in table 2.

Table 1 IP-supported options

-v,-version Print the IP version and exit.
-s,-stats,-statistics output more detailed information. If this option occurs two or more times, the output information will be more detailed.
-f,-family This option is followed by protocol types, including inet, Inet6, or link, which emphasize the type of protocol used. If there is not enough information to tell the IP about the protocol type used, the IP will use the default value inet or any. Link is special, which means that no network protocols are involved.
-4 is a shorthand for-family inet.
-6 is a shorthand for-family Inet6.
-0 is a shorthand for-family link.
-o,-oneline uses a single-line output for each row of records, and the return line is replaced with characters. This option is used if you need to process the output of the IP using tools such as WC, grep, and so on.
-r,-resolve Query the domain name resolution system, replace the host IP address with the host name obtained

COMMAND sets the action performed on the specified object, which is related to the type of the object. In general, IP support objects are added (add), deleted, and displayed (show or list). Some objects do not support these operations, or there are other commands. For all objects, the user can use the Help command for assistance. This command lists the syntax of commands and arguments supported by this object. If you do not specify an action command for an object, IP uses the default command. In general, the default command is list, and if the object cannot be listed, the Help command is executed.

ARGUMENTS are some of the parameters of the command, which depend on objects and commands. IP supports two types of parameters: flag and parameter. Flag is made up of a keyword; parameter consists of a keyword plus a numeric value. For convenience, each command has a default parameter that can be ignored. For example, the parameter dev is the default parameter for the IP link command, so the IP link ls eth0 equals the IP link ls dev eth0. We'll cover the use of each command in more detail later, and the default parameters for the command will be marked with the defaults.

4.1 IP link set--changes the properties of the device. Abbreviation: Set, S

Example 1:up/down starting/shutting down the device.

# IP link set dev eth0 up

This equals the traditional # ifconfig eth0 up (down)

Example 2: Change the length of the device transmission queue.

Parameter: Txqueuelen number or Txqlen number

# IP link Set dev eth0 txqueuelen 100

Example 3: Change the value of the network device MTU (maximum transmission unit).

# IP link set dev eth0 MTU 1500

Example 4: Modify the MAC address of a network device.

Parameter: Address lladdress

# IP link Set dev eth0 address 00:01:4f:00:15:f1

4.2 IP Link show--Displays the device properties. Abbreviation: show, list, LST, sh, LS, l

The-s option occurs two or more times, and IP outputs more detailed error information statistics.

Example:

# ip-s-S link ls eth0

ETH0:MTU Qdisc CBQ Qlen 100

Link/ether 00:a0:cc:66:18:78 BRD FF:FF:FF:FF:FF:FF

Rx:bytes packets Errors dropped overrun Mcast

2449949362 2786187 0 0 0 0

RX Errors:length CRC Frame FIFO missed

0 0 0) 0 0

Tx:bytes packets errors dropped carrier Collsns

178558497 1783946 332 0 332 35172

TX errors:aborted FIFO window heartbeat

0 0 0 332

This command equals the traditional ifconfig eth0.

5.1 IP Address add--Add a new protocol address. Abbreviation: Add, a

Example 1: Set a string for each address as a label. To be compatible with Linux-2.0 's network aliases, this string must start with the device name, followed by a colon,

# IP Addr Add local 192.168.4.1/28 BRD + label Eth0:1 Dev eth0

Example 2: Add an address 192.168.20.0 on the Ethernet interface eth0, a mask length of 24 bits (155.155.155.0), a standard broadcast address, and a label of Eth0:alias:

# IP Addr Add 192.168.4.2/24 brd + dev eth1 label eth1:1

This command equals the traditional: Ifconfig eth1:1 192.168.4.2

5.2 IP Address delete--deletes a protocol address. Abbreviation: Delete, Del, D

# IP Addr del 192.168.4.1/24 BRD + dev eth0 label eth0:alias1

5.3 IP Address show--displays protocol addresses. Abbreviation: show, list, LST, sh, LS, l

# IP Addr ls eth0

5.4.IP address flush--clears protocol addresses. Abbreviation: Flush, F

Example 1: Delete all addresses that belong to the private network 10.0.0.0/8:

# ip-s-S a f to 10/8

Example 2: Canceling the IP address of all Ethernet cards

# ip-4 Addr Flush Label "eth0"

6. IP neighbour--neighbour/arp Table Management commands

Abbreviations neighbour, neighbor, Neigh, n

command Add, change, replace, delete, Fulsh, show (or list)

6.1 IP neighbour Add-adds a new adjacency entry

IP neighbour change--Modifying an existing entry

IP neighbour replace--Replace an existing entry

Abbreviations: Add, A;change, Chg;replace, REPL

Example 1: On the device eth0, add a permanent ARP entry for address 10.0.0.3:

# IP neigh add 10.0.0.3 lladdr 0:0:0:0:0:1 dev eth0 nud Perm

Example 2: Change the status to reachable

# ip neigh chg 10.0.0.3 dev eth0 nud reachable

6.2.ip neighbour delete--Delete an adjacency entry

Example 1: Remove an ARP entry on the device eth0 10.0.0.3

# ip neigh del 10.0.0.3 dev eth0

6.3.ip Neighbour show--Displays information about the Network Neighborhood. Abbreviation: show, list, sh, ls

Example 1: # ip-s n ls 193.233.7.254

193.233.7.254. Dev eth0 lladdr 00:00:0c:76:3f:85 ref 5 used 12/13/20 Nud reachable

6.4.ip neighbour flush--clears the adjacency entry. Abbreviation: Flush, F

Example 1: (-S can show more information)

# ip-s-S n F 193.233.7.254

7. Routing Table Management

7.1. Abbreviated route, RO, R

7.5. Routing table

Starting with Linux-2.2, the kernel induces routes into many routing tables, which are numbered and numbered in the range 1 to 255. Other than that

For convenience, you can also name the routing table in/etc/iproute2/rt_tables.

By default, all routes will be inserted into the table main (number 254). In a routing query, the kernel uses only the routing table main.

7.6.ip route Add--Add new route

IP route Change--Modify route

IP route Replace-replaces existing routes

Abbreviations: Add, A;change, Chg;replace, REPL

Example 1: Set the route to the network 10.0.0/24 through the gateway 193.233.7.65

# IP route add 10.0.0/24 via 193.233.7.65

Example 2: Modify the direct route to the network 10.0.0/24 so that it passes through the device dummy

# ip route chg 10.0.0/24 Dev Dummy

Example 3: Implement link load balancing. Join the default multipath route and let Ppp0 and Ppp1 share the load (note: The scope value is not required, it just tells the kernel,

This route is routed through a gateway rather than directly connected. In fact, if you know the address of the remote endpoint, it's better to use the Via parameter to set it up.

# IP route Add default scope global Nexthop dev ppp0 nexthop Dev ppp1

# IP route replace default scope global nexthop dev ppp0 nexthop Dev ppp1

Example 4: Set up a NAT route. Before forwarding packets from 192.203.80.144, network address translation is performed, and this address is converted to 193.233.7.83

# IP route add Nat 192.203.80.142 via 193.233.7.83

Example 5: Implement packet-level load balancing, allowing packets to be emitted randomly from multiple routes. Weight can set weights.

# IP route replace default equalize nexthop via 211.139.218.145 dev eth0 weight 1 nexthop via 211.139.218.145 Dev eth1 Wei Ght 1

7.7.ip Route delete--Delete route

Abbreviation: Delete, Del, D

Example 1: Remove a multipath route joined by the previous section command

# IP route del default scope global nexthop dev ppp0 nexthop Dev ppp1

7.8.ip Route Show--list routes

Abbreviation: show, list, sh, LS, l

Example 1: Calculate the number of routes using the GATED/BGP protocol

# IP route ls Proto GATED/BGP |WC

1413 9891 79010

Example 2: Calculate the number of bars in the route cache, because the properties of the cached route may be greater than one row, so you need to use the-o option

# ip-o Route LS cloned |WC

159 2543 18707

Example 3: List the routes inside the routing table TableID. The default setting is table Main. TableID is either a real routing table ID or a string defined by the/etc/iproute2/rt_tables file,

or the following special values:

All-Lists the routes for all tables;

Cache--Lists the contents of the route cache.

IP RO ls 193.233.7.82 tab cache

Example 4: Listing the contents of a routing table

# IP route ls table fddi153

Example 5: List the contents of the default routing table

# IP Route ls

This command equals the traditional: route

7.9.ip Route Flush--Erase route table

Example 1: Remove all gateway routes in the routing table main (example: After the routing monitor hangs):

# ip-4 RO Flush Scope Global type unicast

Example 2: Clear all IPv6 routes that are cloned:

# ip-6-s-s RO flush Cache

Example 3: Clear all BGP routes after the gated program has been hung out:

# ip-s ro F Proto GATED/BGP

Example 4: Clear all IPv4 route cache

# IP route Flush Cache

IPV4 routing cache is flushed.

7.10 IP route Get--get a single route. Abbreviation: GET, G

Use this command to obtain a route to the destination address and its exact contents.

The IP route get command and the IP Route show command perform different actions. The IP route Show command simply shows the existing route, and the IP route get command will derive a new route if necessary.

Example 1: Searching for routes to 193.233.7.82

# IP Route Get 193.233.7.82

193.233.7.82 Dev eth0 src 193.233.7.65 Realms inr.ac Cache MTU 300 RTT

Example 2: The Search destination address is 193.233.7.82, from 193.233.7.82, the route that arrives from the eth0 device (this command produces a very interesting route, which is a loopback route to 193.233.7.82)

# IP R g 193.233.7.82 from 193.233.7.82 iif eth0

193.233.7.82 from 193.233.7.82 dev eth0 src 193.233.7.65 Realms inr.ac/inr.ac

Cache <src-direct,redirect> MTU (RTT) IIF eth0

8. IP route--routing policy Database management commands

Command

Add, delete, show (or list)

Note: Policy routing is not equal to the routing policy (rouing).

In some cases, we don't just need to determine the route through the destination address of the packet, but there may also be other domains: The source address, the IP protocol, the Transport layer port, or even the payload of the packet.

This is called: Policy Routing.

8.5. IP rule Add-Inserts a new rule

IP Rule Delete--delete rule

Abbreviations: Add, A;delete, Del, D

Example 1: Route a packet from the source address 192.203.80/24 by routing table Inr.ruhep

IP ru add from 192.203.80/24 table Inr.ruhep Prio 220

Example 2: Convert the source address of a datagram with a source address of 193.233.7.83 to 192.203.80.144 and route through table 1

IP ru add from 193.233.7.83 nat 192.203.80.144 table 1 Prio 320

Example 3: Delete a useless default rule

IP ru del prio 32767

8.7. IP rule Show--list routing rules

Abbreviation: show, list, sh, LS, l

Example 1: # IP ru ls

0:from All lookup Local

32762:from 192.168.4.89 Lookup fddi153

32764:from 192.168.4.88 Lookup fddi153

32766:from All lookup Main

32767:from All Lookup 253

9. IP maddress--Multicast address management

Abbreviation: show, list, sh, LS, l

9.3.ip maddress Show--list multicast addresses

Example 1: # IP maddr ls Dummy

9.4. IP maddress Add-Join a multicast address

IP maddress Delete--Remove multicast address

Abbreviations: Add, A;delete, Del, D

With these two commands, we can add/remove the link-layer multicast address that is listening on the network interface. This command only manages link-layer addresses.

Example 1: Add # ip maddr add 33:33:00:00:00:01 dev Dummy

Example 2: View # ip-o maddr ls Dummy

2:dummy

Link 33:33:00:00:00:01 users 2 static

Link 01:00:5e:00:00:01

Example 3: Remove # ip maddr del 33:33:00:00:00:01 dev Dummy

10.ip Mroute--Multicast routing cache management

10.4. IP mroute Show--list multicast route cache entries

Abbreviation: show, list, sh, LS, l

Example 1: View # IP Mroute ls

(193.232.127.6, 224.0.1.39) Iif:unresolved

(193.232.244.34, 224.0.1.40) Iif:unresolved

(193.233.7.65, 224.66.66.66) Iif:eth0 Oifs:pimreg

Example 2: View # ip-s Mr Ls 224.66/16

(193.233.7.65, 224.66.66.66) Iif:eth0 Oifs:pimreg

9383 packets, 300256 bytes

IP tunnel--channel configuration

Abbreviation

Tunnel, TUNL

11.4.ip Tunnel Add-adds a new channel

IP Tunnel Change-modifies an existing channel

IP Tunnel Delete--Deletes a channel

Abbreviations: Add, A;change, Chg;delete, Del, D

Example 1: Establish a point-to-point channel with a maximum TTL of 32

# IP tunnel Add Cisco mode sit remote 192.31.7.104 local 192.203.80.1 TTL 32

11.4.ip Tunnel Show--list existing channels

Abbreviation: show, list, sh, LS, l

Example 1: # ip-s TUNL ls Cisco

IP monitor and Rtmon-Status monitoring

IP commands can be used to continuously monitor the status of devices, addresses, and routes. The format of this command option is a bit different, the command option is named Monitor, followed by the operand:

IP monitor [file file] [all | Object-list]

Example 1: # Rtmon File/var/log/rtmon.log

Example 2: # IP monitor File/var/log/rtmon.log r

Linux Network integrated Command--IP