（1） display version
display version命令是最基本的命令之一，它用于显示路由器硬件和软件的基本信息。因为不同的版本有不同的特征，实现的功能也不完全相同，所以，查看硬件和软件的信息是解决问题的重要一步。在进行故障处理时，我们通常从这个命令开始收集数据。该命令将帮助用户收集下列信息：
l VRP软件版本
l 是哪一系列的路由器
l 处理器的信息
l RAM的容量
l 配置寄存器的设置
l 固件的版本
l 引导程序的版本
输出示例如下，请找到上述提及的相应项。
[Router]display version
Copyright Notice:
All rights reserved (Aug 12 2003).
Without the owner's prior written consent, no decompiling
or reverse-engineering shall be allowed.
Huawei Versatile Routing Platform Software
VRP (R) software, Version 1.74 Release 0101
Copyright (c) 1997-2003 HUAWEI TECH CO., LTD.
Quidway R1760 uptime is 0 days 5 hours 33 minutes 19 seconds
System returned to ROM by power-on.
Quidway R1760 with 1 MPC 8241 Processor
Router serial number is 00E0FC0F62563402
64M bytes SDRAM
8192K bytes Flash Memory
0K bytes NVRAM
Config Register points to FLASH
Hardware Version is MTR 1.0
CPLD Version is CPLD 1.0
Bootrom Version is 4.69
[LAN ] 1FE Hardware Version is 2.0, Driver Version is 2.0
[AUX ] AUX Hardware Version is 1.0, Driver Version is 1.0,
Cpld Version is 1.0
[WAN ] WAN Hardware Version is 1.0, Driver Version is 1.0,
Cpld Version is 1.0
[SLOT 0] E1VI Hardware Version is 1.0, Driver Version is 1.8
（2） display current-configuration
display current-configuration命令用于显示目前路由器上已经做的配置，这可以说是排除故障的重要起点。
例如
[Router]display current-configuration
Now create configuration...
Current configuration
!
version 1.74
local-user a service-type administrator password simple a
firewall enable
undo login-method authentication-mode async
undo login-method authentication-mode con
undo idle-timeout
!
controller e1 0
!
interface Aux0
undo modem
async mode flow
flow-control none
link-protocol ppp
!
interface Ethernet0
!
interface Serial0
link-protocol ppp
!
voice-setup
!
quit
!
quit
snmp-agent
snmp-agent local-engineid 800007DB0300E0FC0F6256
snmp-agent community read a
snmp-agent community write b
snmp-agent sys-info version all
!
return
（3） display interface命令
display interface命令可以显示所有接口的当前状态，如果只是想查看特定接口的状态，请在该命令后输入接口类型和接口号，例如：display interface serial 0命令将查看串口0的运行状态和相关信息。
[Router]display interface serial 0
Serial0 current state:up, line protocol current state:up
The Maximum Transmit Unit is 1500
physical layer is synchronous, baudrate is 64000 bps
interface is DCE, clock is DCECLK, cable type is V35
Link-protocol is PPP
LCP opened, IPCP initial, IPXCP initial, CCP initial, BRIDGECP initial
Input queue : (size/max/drops) 0/50/0
FIFO queueing: FIFO
(Outbound queue:Size/Length/Discards)
FIFO: 0/75/0
Last 5 minutes input rate 0.00 bytes/sec, 0.00 packets/sec
Last 5 minutes output rate 0.00 bytes/sec, 0.00 packets/sec
Input: 7 packets, 102 bytes
0 broadcasts, 0 multicasts
0 errors, 0 runts, 0 giants
0 CRC,0 frame errors, 0 overrunners
0 aborted sequences 0 no buffers
0 packets with dribble condition detected
Output:6 packets, 84 bytes
0 broadcasts, 0 multicasts
0 errors, 0 underruns, 0 collisions
0 packets had been deferred
DCD=UP DTR=UP DSR=UP RTS=UP CTS=UP
在上面的显示中,主要包括了三方面内容，物理接口的信息：包括接口速率、线缆、MTU、监听的信号状态；链路层协议（LCP）和三层协议（IPCP）的状态；接口接收发送数据包的统计值（Input,Output）.这些信息对排查联通性的问题都是必需的。
1.2.2 ping命令
（1）原理
“ping”这个词源于声纳定位*作，指来自声纳设备的脉冲信号。ping命令的思想与发出一个短促的雷达波，通过收集回波来判断目标很相似；即源站点向目的站点发出一个ICMP Echo Request报文，目的站点收到该报文后回一个ICMP Echo Reply报文，这样就验证了两个节点间IP层的可达性－－表示了网络层是连通的。
（2）功能
命令ping用于检查IP网络连接及主机是否可达。
（3）VRP平台的ping命令
在Quidway系列路由器上， ping命令的格式如下：
[Router]ping -?
usage: ping [-R dnqrv] [-a IP-address] [-c count] [-o IP-TOS] [-p pattern]
[-s packetsize] [-t timeout] [-i TTL] host
options:
-a IP address Source IP address
-c count Number of echo requests to send
-d Set the SO_DEBUG option on the socket being used
-f Set the DF flag in IP header
-n Numeric output only.No attempt will be made to
lookup symbolic names for host addresses
-o IP-TOS Set the TOS in IP header
-p pattern You may specify up to 16 "pad" bytes to fill
out the packet you send. For example, -p ff will
cause the sent packet to be filled with all ones
-q Quiet output. Nothing is displayed except the
summary lines at startup time and when finished
-R Record route. Includes the RECORD_ROUTE option in
the ECHO_REQUEST packet and displays the route
buffer on returned packets
-r Bypass the normal routing tables and send directly
to a host on an attached network
-s packetsize Specifies the number of data bytes to be sent
-t timeout Timeout in milliseconds to wait for each reply
The default is 56
-v Verbose output. ICMP packets other than ECHO_RESPONSE
that are received are listed
-i TTL Time to live
例如，向主机10.15.50.1发出2个8100字节的ping报文
Quidway# ping -c 2 -s 8100 10.15.50.1
PING 10.15.50.1: 8100 data bytes, press CTRL_C to break
Reply from 10.15.50.1: bytes=8100 Sequence=0 ttl=123 time = 538 ms
Reply from 10.15.50.1: bytes=8100 Sequence=1 ttl=123 time = 730 ms
--- 10.15.50.1 ping statistics ---
2 packets transmitted
2 packets received
0.00% packet loss
round-trip min/avg/max = 538/634/730 ms
（4）Windows平台的ping命令
在PC机上或Windwos NT为平台的服务器上，ping命令的格式如下：
ping [ -n number ] [ -t ] [ -l number ] ip-address
-n ping报文的个数，缺省值为5；
-t 持续地ping 直到人为地中断，Ctr+Breack暂时中止ping命令并查看当前的统计结果，而Ctr+C则中断命令的执行。
-l 设置ping报文所携带的数据部分的字节数，设置范围从0至65500。
例：向主机10.15.50.1 发出2个数据部分大小为 3000 Bytes的ping报文
C:\> ping -l 3000 -n 2 10.15.50.1
Pinging 10.15.50.1 with 3000 bytes of data
Reply from 10.15.50.1: bytes=3000 time=321ms TTL=123
Reply from 10.15.50.1: bytes=3000 time=297ms TTL=123
Ping statistics for 10.15.50.1:
Packets: Sent = 2, Received = 2, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 297ms, Maximum = 321ms, Average = 309ms
