Network Foundation Cisco Routing switch One

VLAN overview

Virtual LANs are a logical group of users who are linked on physical devices that are not subject to physical location restrictions.

Reference VLAN:

The switch divides the conflict domain, but cannot divide the broadcast domain, as the number of switch ports increases, the broadcast in the network increases, the network efficiency is reduced, and the VLAN is introduced in order to split the broadcast domain.

Advantages of VLANs:

Broadcast control.

Broadband use.

Delay decreased.

Security improvements.

VLAN type:

Static VLAN: A static VLAN based on port partitioning.

Dynamic VLAN: Dynamic VLAN based on MAC address partitioning.

Two methods of configuring VLANs:

Switch#vlan database (into VLAN databases)

Switch (VLAN) #vlan 2 name xxx (create vlan2 and change name to XXX)

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Switch (config) #vlan 3 (Create VLAN 3)

Switch (Config-vlan) #name x (change name to X)

To delete a VLAN:

Switch#vlan database (enter VLAN or switch (config) # no vlan2 (global variable is deleted directly))

Switch (VLAN) #no VLAN 2 (delete vlan2)

The bulk interface joins the VLAN:

Switch (config) #interface range F0/1-2 (check 1.2 port number)

Switch (config-if-range) #switchport Access VLAN 3 (Connect 1.2 ports to VLAN3)

Interface joins VLAN:

Switch (config) #interface fastethernet 0/1 (enter Port 1th)

Switch (config-if) #switchport Access VLAN 2 (Configure the 1th interface into vlan2)

Trunk Trunk Link:

Implement VLAN communication across switches

Trunk links can host multiple VLANs

Identity of the VLAN:

ISL (Cisco private Tag method)

ISL Outer Package Header 26 Bytes, trailing 4 bytes, total 30 bytes

IEEE 802.1q (public tagging method)

The internal package inserts 4 bytes within the standard Ethernet frame, where the 12-bit VLAN is identified.

ISL and 802.1q similarities and differences:

Same as: both show VLAN information.

Vary

IEEE 802.1q is a public marking method, the ISL is Cisco private.

ISL uses an external tag method, and 802.1q uses an internal tag method.

The ISL tag is 30 bytes long and the length of the 8021q tag is 4 bytes.

Trunk Configuration

Switch (config) #interface fastethernet 0/15 (enter 0/15 interface)

Switch (config-if) #switchport mode trunk (configured as trunk mode)

Switch (config) #interface fastethernet 0/15 (enter 0/15 interface)

Switch (config-if) #switchport mode dynamic desirable (configured for dynamic Hope)

Switch (config) #interface fastethernet 0/15 (enter 0/15 interface)

Switch (config-if) #switchport mode dynamic auto (Dynamic Auto)

To remove a VLAN from a trunk link:

Switch (config-if) # (Enter interface)

Switch (config-if) #switchport trunk allowed VLAN remove 2 (relay link does not allow the transfer of VLAN2 data)

To add a VLAN on a teunk link:

Switch (config-if) # (Enter interface)

Switch (config-if) #switchport trunk allowed VLAN add 2 (add vlan2)

To view the interface mode:

Switch#show Interfaces F0/5 switchport (view port 5th)

Ethernet Channel:

Also known as Ethernet port bundle, Port aggregation or Ethernet link aggregation, English name EtherChannel,

The Ethernet channel provides the switch with port bundling technology that allows two switches to connect to one or more ports in parallel, while transmitting data to improve bandwidth.

Multi-line load balancing, when one line fails, other lines communicate, do not lose packets,

Configuration of the Ethernet channel:

Switch (config) #interface range f0/x-X (x-x port selected)

Switch (config-if-range) #switchport mode trunk (Configure Port to trunk mode)

Switch (Config-if-range) #channel-group 1 mode on (open channel)

Configure the DHCP service on the router

Router (config) #

Router (config) #ip DHCP pool Hydra (define an address pool)

Router (dhcp-config) #network 192.168.1.0 255.255.255.0 (dynamically assigned IP address segment)

Router (dhcp-config) #default-router 192.168.1.254 (dynamically assigned gateway address)

Router (dhcp-config) #dns-server 202.106.0.20 (dynamically assigned DNS server address, secondary command can be followed by multiple alternate DNS addresses)

Switch (config) #ip dhcp excluded-address 192.168.1.1 (reserved statically assigned IP address)

Network Foundation Cisco Routing switch One