VLAN
If two or more switches are directly connected and a lot of devices are connected, a broadcast storm will be directly formed for the first time, which will affect each other. Therefore, the broadcast domain needs to be divided.
There are two partitioning methods:
physical partitioning (router)
logical partitioning (VLAN) implementation through switch software.
We generally use software to partition a network
VLAN essentially refers to a network segment. The reason why it is called a virtual local area network is because it is virtual. The
advantages of the network segment created under the router interface :
1. Control the broadcast domain (we can control the size of the broadcast domain by configuring VLANs)
2. Increase network security
3. Simplify network management
. VLANs are generally divided into static VLANs and dynamic VLANs.
Static VLAN:
Divide static VLAN based on the specific port of the switch. Generally, a VLAN can be divided into multiple ports or a single VLAN.
Dynamic VLAN:
here is a dynamic VLAN based on the MAC address of each connected device.
We generally use static VLANs, that is, the network ports of fixed switches are assigned specific VLANs. If the dynamic VLAN setting is unstable, it will often change. Not conducive to management.
The following figure shows the schematic diagram and table of static VLAN. We can find that VLAN can correspond to the
VLAN range of multiple switch port numbers. The range
is 0~4095 as shown in the figure below. 0 and 4095 are reserved and cannot be used. The
default VLAN is 1, and number 1 can be used but cannot be deleted.
The range of 2~4094 needs to be created manually and can be deleted.
The available VLAN range is: 1~4094
. Initially configure VLAN in eNSP
How to realize VLAN communication between switches.
Access link: the connection between the host and the switch. The
process of labeling and removing the label. The interface on the switch side is configured as an ACCESS
trunk link: the connection between the switch and the switch is
verified by the label and The process of forwarding. The interface between the trunks is configured as a trunk. The
following are some VLAN instructions, just for reference and exercise.
