3com 5500G ユーザーズマニュアル

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HAPTER

 13: A

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 D

ETECT

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ONFIGURATION

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UIDE

You can implement VLAN interface backup through auto detect. When data can 
be transmitted through two VLAN interfaces on the switch to the same 
destination, configure one of the VLAN interfaces as the active interface and the 
other as the standby interface. Through the auto detect function, the standby 
interface is enabled automatically when the active fails, so as to ensure the data 
transmission:

■

In normal situations (that is, when the detected group is reachable), the 
standby VLAN interface is down and packets are sent to the destination 
through the active VLAN interface.

■

When the communication between the active VLAN interface and the 
destination fails (that is, the detected group is unreachable), the system 
enables the backup VLAN interface.

■

When the communication between the active VLAN interface and the 
destination resumes, the system shuts down the standby VLAN interface again.

Figure 21   Network diagram of applying auto detect to VLAN interface backup

 

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Make sure that there is a route between Switch A and Switch B, Switch B and 
Switch C, Switch A and Switch D, and Switch D and Switch C.

■

Create detected group 10 on Switch A to detect the connectivity between 
Switch A and Switch C.

■

Configure VLAN-interface 1 to be the active interface, which is enabled when 
the detected group 10 is reachable.

■

Configure VLAN-interface 2 to be the standby interface, which is enabled 
when the detected group 10 is unreachable.

■

Create detected group 9 on Switch C to detect the connectivity between 
Switch C and Switch A.

■

Configure VLAN-interface 2 to be the active interface, which is enabled when 
the detected group 9 is reachable.

■

Configure VLAN-interface 1 to be the standby interface, which is enabled 
when the detected group 9 is unreachable.

Vlan- int1

192 .168.1.2 /24

Vlan- int2
10.1.1 .3/24

Vlan -int2
10 .1.1.4/24

Vlan -int2
192 .168.3.1/24

Host A

Host C

Switch B

Switch A

Switch C

Switch D

Vlan -int1

192.168 .1.1/24

Vlan -int2

192 .168.3.2 /24

Vlan-int1
10.1.2 .2/24

Vlan- int1

10.1.2.1 /24