User manual

Network Setup

Once the Internet connections have been configured, specify the conditions under which

the Internet connections are established.

Internet Failover

Note

If you have configured your SG560, SG565 or SG580’s switch as separate ports, and are

establishing multiple PPPoE ADSL Internet connections using two or more of these ports,

it is important that each port is connected to a remote device with a unique MAC address.

This is almost definitely the case if each of the Internet connections are through different

ISPs, otherwise you may have to request this specifically from your ISP.

If this is not possible, set each of the ADSL modems to routing or NAT rather than

bridged mode. Typically this means the ADSL modem terminates the PPPoE

connection, and the SG appliance is configured with DHCP or manually assigned

settings, using the ADSL modem as a gateway.

SG units support three connection levels. A connection level consists of one or more

Internet connections. When all primary connections are functioning as expected, the

primary connection level is deemed to be up.

If one or more of the primary connections should fail, the SG unit drops back to the

secondary connection level. This typically involves bringing up a secondary Internet

connection, until the primary Internet connection or connections become available again.

You may also optionally configure the tertiary failover level. If one or more of the

secondary connections should fail, the SG unit drops back to the tertiary connection level.

This is typically a “last resort” dialup link to the Internet, but may be any kind of network

connection. The primary connection level and secondary connection level are tested in

turn, until one becomes available.

Note

Internet failover is not stateful, i.e. any network connections that were established

through the failed primary connection must be re-established through the secondary

connection.