Summarization of interface configuration

Summarization

Supported interface types

Introductions to interface configuration

Introductions to sub-interface

Configure interface public attribute

Monitor and maintain interface

Examples of interface configurations

 

Summarization

Information in summarization will help users to know the types of interfaces supported by our router, and to know different configuration information to different interface.

If you want to know more details about interface instructions , please refer to“interface configurations instructions”. If you want to read document about other instructions appearing in this article, refer to other parts in this manual.

This summarization include public information adapt to all types interfaces, contents are as follows:

supported interface types

introductions to interface configuration

introductions to sub-interface

  configure interface public attribute

monitor and maintain interface

examples of interface configurations

 

Supported interface types

Information about a kind of interface, please refer to format below:

Types of interface

task

Content for reference

LAN interface

l         configure Ethernet interface

l       configure quick Ethernet interface

configure LAN interface”

Serial interface

l       configure synchronization serial interface

l       configure low-speed serial interface

configure serial interface”

Logic interface

l       back loop interface

l       null interface

l       dial interface

l       Virtual template and virtual access interface

l       Multilink interface

l       Tunnel interface

l       Sub-interface

“configure logic interface”

E1interface

Configure channel E1interface

configure E1 interface”

T1interface

Configure channel T1interface

configure T1 interface”

PRI interface

Configure PRI interface

Configure PRI interface”

BRI interface

Configure BRI interface

Configure BRI interface”

DTU interface

Configure DTU interface

Configure DTU  interface”

MODEM interface

Configure MODEM interface

Configure MODEM interface”

 

 

   Our routers support two kinds of interfaces: physical interface and virtual interface. Types of physical interface depend on standard communication interfaces and interface cards or interface module installed in router. Virtual interface include sub-interface and logic interface. sub-interface is derived from physical interface, if you want to know more details ,please refer to “ introduction of sub-interface”. Logical interface does not exist corresponding physical interface, it needs user to create by hands.   

physical interfaces of our routers include:

· Ethernet

· quick ethernet

· synchronization serial

· lowspeed serial

· asychronism serial

· channel E1  

· channel T1  

· ISDN BRI interface  

· ISDN PRI interface  

· DTU interface  

· asychronism MODEM interface  

 

logical interfaces Supported by our routers include

· back loop interface

· null interface

· dial interface

· Virtual template and virtual access interface

· Multilike interface

· Tunnel interface

· sub-interface

Introduction to interface configuration

configurations described below are adapt to all interfaces. You should configure by steps below in overall configurations mode.

1.                You begin to configure interface after entering interface configure mode by “interface” instruction, prompt of router change to “config”, adding the brief name of interface you will configure. You should use these interfaces by serial number, these numbers are assigned when out of product line or at the time that interface card was installed into system. You can use “show interface “to show these interfaces.  Every interface will provide his own state, just like photos below:

Router#show interface

Serial 1/0 is administratively down, line protocol is down

Hardware is SCC Mode=Sync,Speed=64000

DTR=UP,DSR=DOWN,RTS=DOWN,CTS=DOWN,DCD=DOWN

MTU 1500 bytes, BW 64 kbit, DLY 20000 usec

Encapsulation HDLC, loopback not set

Keepalive set(10 sec)

if you want to configure serial interface 1/0, you should input contents as follows:

interface serial 1/0

Now, router prompts “config_s1/0”。

NOTE: you can not add null space between interface types and interface serial number. for an example, serial 1/0 or serial 2/0 both can be accepted by router.

2.   you can configure interface configure instructions to current interface in interface configuration mode. These instructions define negotiations and programs to interface. These instructions will last for always until out of interface configuration mode or switch to another interface.

3.     once finished interface configurations ,you can use “show” to test interface state ,this instruction is discussed in “monitor and maintain interface”.

Note: configure channel E1 interface need other steps. When to configure channel T1 or E1, you need to define channel and time interval made into channel first. You can use  controller E1 and channel-group configure instructions; then use “interface serial “to configure serial interface.

Introduction to sub-interface

If we configure multiple sub-interfaces to a physical interface, that can make interface have a more flexibility and connexity on network. Sub-interface is a setting to support a single physical interface to connect multiple logic interfaces or part networks . That is to say, some logic interfaces and part networks can be connected by a single hardware interface. Sub-interface is used in different www protocol, including frame relay and  X.25 protocol. 

Configure interface public attribute

Instructions below can be executed in any kind interface, to configure interface public attribute . You can configure such public attribute,including: 

·     add discriptions

·     set band width

·   set time delay

·     resize MTU

add discriptions

It is helpful to remember interface content to add descriptions about interface. This discription is only a interface note, and it help users to know uses of interface but not affect any function of interface. This discription will appear in output below: show running-config and show interface。If you want to add a discription to any interface, use instruction below in interface configuration mode.

Instrction

purpose

description string

Add descriptions to current cinfigure interface

  For an example of adding descriptions to interface, refer to examples of interface descriptions.

 

set band width

Father protocol use band width to decide operation. You can use instructions below to set band width for interface.

 

Instruction

purpose

bandwidth kilobps

Set band width for current interface

This setting is only a route parameter, it will not affect communication speed of a physical interface.  

Set time delay

Father protocol use time delay to decide operation. You can use instructions below to set time delay for interface.

  

instruction

purpose

delay tensofmicroseconds

Set band width for current interface

The setting of time delay is only a parameter, it will not affect real time delay of a interface.

 

Resize MTU

There is a default MTU of each interface. This default is often 1500 bytes. In serial interface, MTU changes as settings, but it can not be less than 68 bytes. You can use instructions below to resize MTU:

instruction

purpose

mtu bytes

Set MTU for current interface

   

Monitor and maintain interface

You can monitor and maintain interfaces through tasks below:

 

check interface

Our router support instruction to show much information of interface , including versions of software and hardware, interface state. There are part interface monitor instructions in following format. Refer to “interface configuration instructions”.

Use following instructions:

instruction

purpose

show interface [type slot/port]

Show interface state

show running-config

Show running configuration

Show version

Show hardware configurations, software version, name and source of configuration file and startup image

   

initialize and delete interface

  User can dynamic create ,dynamic delete logic interface. You can dynamic delete sub-interface and channel interface. You can renew default configurations to logic interfaces which can not be dynamic deleted. You can use following instructions to initialize and delete interfaces in overall situation configuration mode.

instruction

purpose

no interface type slot/port

Initialize logic interface and delete virtual interface

   

shutoff and restart interface

You can disabled a interface and all its functions ,and this interface will be signed “disabled interface”. This information can be transmit to other routers by dynamic route protocol. You will not involve this interface whatever you change any route. But if it is a serial interface, it will reduce DTR if your stop a interface. 

You can use following instructions to shut off a interface in interface configuration mode, then restart it:

step

instruction

purpose

1

shutdown

Disabled interface

2

No shutdown

Restart interface

If you want to check whether a interface is “disabled” or not, you can use “show interface” and “show running-config”。When using “show interface”, a disabled interface will show ”administratively down”. Refer to examples of ”examples of disabled interface”.  

Examples of interface configurations

There are some examples about:

·        an example of start interface

·        an example of interface description

·        an example of disabled interface

 

an example of start interface

The following example will explain how to begin to configure a interface on a serial interface. It will encapsulate PPP to serial interface 1/0.

interface serial 1/0

encapsulation ppp

an example of interface description

The example following will discuss how to add interface description, such a description will appear in configuration file and interface instructions show.

interface ethernet 1/1

description First Ethernet in network 1

ip address 192.168.1.23 255.255.255.0

 

an example of disabled a interface

The example following will disabled a Ethernet interface 1/1 

interface ethernet 1/1

shutdown

 

The example following will restart interface

interface ethernet 1/1

no shutdown

The example following will disabled a E1

interface serial 1/3:23

shutdown