The basic principle and configuration of the switch (eNSP basic command operation)
data link layer
Located between the network layer and the physical layer
Ethernet: working at the data link layer
The development of Ethernet
X-Wire: 2.94M experimental Ethernet
DIX: 10M Ethernet application
IEEE802.3: 10M Ethernet standard
Gigabit Ethernet: 100/ 1000M Ethernet
Ethernet MAC address
Used to identify a single device or a group of devices on an Ethernet. The
MAC address consists of 48 binary numbers, usually divided into six segments. The
first 24 bits are used as supplier identification in hexadecimal , and the last 24 bits are The vendor’s unique number
for the network card. For the destination address, 0 means logical address (unicast address), 1 means logical address (multicast address)
Ethernet frame format
Ethernet II frame format
preamble (7 bytes) + frame start delimiter (1 byte) + destination address (6 bytes) + source address (6 bytes) + type (2 bytes) + data (46 -1500 bytes) + frame check sequence (4 bytes)
where type is used to identify the type of upper layer protocol, for example, 0800H means IP protocol, 0806H means ARP protocol. The
whole is the physical layer encapsulation
destination address-frame check sequence is data Link layer encapsulation
How the switch works
1. Learning based on the source MAC address
2. Forwarding based on the known destination MAC address
3. When the destination MAC address is unknown, flood processing
4. When the switch receives a broadcast/multicast frame, unconditional flood processing
5. One interface of the switch can Learning multiple MAC addresses
6. The switch learns the same MAC address, but it is learned from different ports. At this time, bind this MAC with the later learned port
The working mode of the switch Ethernet interface
Simplex: Two data stations can only transmit data in a single direction.
Half-duplex: Two data stations can transmit data in both directions, but not at the same time.
Full duplex: Two data stations can be bidirectional and simultaneously. Data transmission
Switch Ethernet interface rate
Negotiation when interface is connected,
normal communication will not be possible if negotiation fails
Preparation before configuration
Connect the
console cable before configuration
Physical connection:
computer COM port
switch/router console port
Software connection:
HyperTerminal
Other software
eNSP basic operating instructions
Switch user view mode to system view mode [Huawei]
system-view
History command query
[Huawei] display history-command
Configure the host name
system-view
[Huawei] sysname Router1
Status information query
display version ####View VRP version
display users ####View user terminal information
Enter interface mode and view information
sys
[Huawei]int e0/0/1
[Huawei-GigabitEthernet0/0/1]dis this ####View the configuration information in the current view
Configuration file management command
[Huawei]display saved-configuration ###View the information saved on the device
[Huawei]display current-configuration ###View the information on the current configuration of the device
reset saved-configuration ###Erase the configuration file in the storage device
compare configuration ###Compare whether the current configuration information is consistent with the saved file in the storage device
Turn off Huawei's information prompt center
[Huawei] undo info-center enable
or
undo terminal monitor
Eternal time
[Huawei] user-interface console 0
[Huawei-ui-console0] idle-timeout 0 0
Configure the duplex and speed command
sys
[Huawei]int g0/0/1
[SW1-Ethernet0/0/1]undo negotiation auto ###Turn off auto negotiation
[SW1-Ethernet0/0/1]speed 100 ###adjust to Speed 100M
[SW1-Ethernet0/0/1]duplex full ###Adjust to full-duplex mode, explanation: full: Full-Duplex (full-duplex mode) half: Half-Duplex (half-duplex mode)
Save configuration
save
Set the remote login password
[Huawei]user-interface vty 0 4 #0 is the initial value, 4 is the end value. Means that you can open 5 sessions at the same time to enter the switch to configure the command
[Huawei-ui-vty0-4]authentication-mode password
[Huawei-ui-vty0-4]set authentication password simple 222
[Huawei-ui-vty0-4]user privilege level 3
[Huawei-ui-vty0-4]dis this
Use SecureCRT to link eNSP
●Double-click to open a device with [View] and [Configuration], open [Configuration] —window configuration: serial port number: 2000 ###This is the port number
●Open SecureCRT and click [link]—[Protocol] Telnet ----【Hostname】127.0.0.1----【Prot】2000
●The current terminal is opened—disconnected【disconnect】----session【session options】————Force one character at a time mode【 Force charater at atime mode]—Save【OK】
●Right click on the current terminal—link【reconnect】