Hello @User95478885,
these modes are all described very well in the 9.2 product guide which can be downloaded here:
https://contentsecurity.mcafee.com/documentation_mwg7
Here copied out of the guide (contains below description + network diagram screenshot):
Next-hop proxy modes
When multiple servers are available as next-hop proxies for routing requests, the next-hop proxy module can use several modes
to call them: Round-robin, failover, and stickiness.
Round-robin mode for next-hop proxies
When routing a request in round-robin mode, the next-hop proxy module calls the next-hop proxy that is next on the list to the
one that was called last time.
McAfee Web Gateway 9.2.x Product Guide 295
For the next request, this is handled in the same way, so all servers on the list will eventually have been used as next-hop proxies.
The following diagram shows a next-hop proxy configuration in round-robin mode.
Failover mode for next-hop proxies
When routing a request in failover mode, the next-hop proxy module calls the first next-hop proxy on the list.
If this next-hop proxy fails to respond, the call is repeated until the configured number of retries is reached. Only then is the
second next-hop proxy in the list tried. It is called in the same way as the first, and eventually the third next-hop proxy in the list
is tried.
This is continued until a next-hop proxy responds or all next-hop proxies in the list were found to be unavailable.
The following diagram shows a next-hop proxy configuration in failover mode.
Next-hop proxy stickiness
A next-hop proxy can also be selected according to what is known as the "sticky" mode. In this mode, requests of a particular
kind, for example, requests coming in from the same client of Web Gateway are directed to the same next-hop proxy.
The part of a request that qualifies it for being handled in sticky mode is configured as the value of a property on Web Gateway.
An event in a rule sets the property to this value.
The name of the property that is configured to enable next-hop proxy stickiness is NextHopProxy.StickinessAttribute. If you want, for
example, to let requests from the same client be directed to the same next-hop proxy, you can use the IP address of a client as
the value for this property.
In addition to creating a rule, you must also select stickiness as an option within the settings for handling next-hop proxies. The
settings also include an option for limiting the time that the next-hop proxy stickiness mode is applied.
Regards,
Marcel Kutrieba
Technical Support Engineer
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