Internet Failover - Secure Computing SG300 User Manual

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.
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Network Setup