Load Balancing; Enabling Load Balancing - McAfee SG310 Administration Manual

Network Setup menu options
Internet connection failover
[Optional] Select a Tertiary failover for yet another port or ports.
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[Optional] Select the Load Balance checkbox to enable load balancing for two or more ports. For more
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information, see Load
Click Finish.
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Load balancing

Once you have configured two or more Internet connections, you can enable Internet load balancing. Load
balancing can be used in conjunction with Internet connection failover or on its own to specify the
connection as the preferred gateway.
Load balancing settings are not specified for each failover level; load balancing occurs when any two or
more load balancing connections are up. The Internet connections need not be the same; for example, you
can enable load balancing between a PPPoE ADSL connection on one network port, and a Cable Internet
connection on the other.
Limitations of load balancing
Load balancing works by alternating outgoing traffic across Internet connections in a round-robin manner.
It does not bond both connections together to work as one link; that is, it does not bond two 512 Kbit/s
links to function as a single 1 Mbit/s link. Total bandwidth and available bandwidth are not taken into
account when choosing a connection on which to send outgoing traffic.
When an internal client makes a connection to a server on the Internet, this and subsequent connections
between the internal client and remote server are confined to the one Internet connection to ensure
connections are not broken. If a second internal client makes a connection to the same remote server, it
may or may not go across the same link, depending on which Internet connection is selected next in the
process. VPN connections such as IPSec or PPTP tunnels are confined to a single Internet connection, as
they are a single connection that encapsulates other connections.
Load balancing is not performed for incoming traffic. This scenario can be addressed using other solutions
such as round-robin DNS to alternate incoming connections between the two links.

Enabling load balancing

Use this procedure to enable load balancing by designating one or more connections as preferred gateways.
You can designate any configured Internet connection as a preferred gateway.configure load balancing for
any configured Internet connection. All active Internet connections with load balancing enabled become
preferred gateways. If only one Internet connection is enabled, it becomes the preferred gateway. If two or
more connections are enabled for load balancing, traffic is balanced equally across those connections.
If there are multiple internet connections and none have been selected as preferred gateways, a warning is
displayed (Figure 74).
McAfee UTM Firewall 4.0.4 Administration Guide
balancing.
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