Chapter 12 Trunks

12.1.2What You Need to Know

Add WAN interfaces to trunks to have multiple connections share the traffic load.

If one WAN interface’s connection goes down, the ZyWALL sends traffic through another member of the trunk.

For example, you connect one WAN interface to one ISP and connect a second WAN interface to a second ISP. The ZyWALL balances the WAN traffic load between the connections. If one interface's connection goes down, the ZyWALL can automatically send its traffic through another interface.

You can also use trunks with policy routing to send specific traffic types through the best WAN interface for that type of traffic.

If that interface’s connection goes down, the ZyWALL can still send its traffic through another interface.

You can define multiple trunks for the same physical interfaces.

Link Sticking

You can have the ZyWALL send each local computer’s traffic that is going to the same destination through a single WAN interface for a specified period of time. This is useful when a server requires authentication. For example, the ZyWALL sends a user’s traffic through one WAN IP address when he logs into a server B. If the user’s subsequent sessions came from a different WAN IP address, the server would deny them. Here is an example.

Figure 168 Link Sticking

1

 

 

 

 

 

B

wan1

2

3

 

 

wan2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

LAN

A

1LAN user A logs into server B on the Internet. The ZyWALL uses wan1 to send the request to server B.

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ZyWALL USG 50 User’s Guide