User guide

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Scheduling method:
The scheduling method is the way in which traffic is distributed among the servers in the
farm. Eight different methods are supported. If you are using a shopping cart service, a
persistent scheduling method is recommended.
Least connections
Least connections—persistent
Round robin
Round robin—persistent
Weighted least connections
Weighted least connections—persistent
Weighted round robin
Weighted round robin—persistent
Weighted fastest response
Weighted fastest response—persistent
Faster Layer 7 HTTP URI load directing (no compression)
Layer 7 HTTP URI load directing
Layer 7 HTTP URL load directing with cookies
Layer 7 HTTP cookie load directing with cookies
Layer 7 HTTP virtual host load directing with cookies
Layer 7 generic TCP load directing
Layer 7 scheduling methods can only be used with TCP service. These scheduling methods
allow you to direct traffic to a specific group of servers depending on a match pattern that is
tested against the URI in the client’s GET request header. When selecting any of L7
scheduling method, user can also enable IPV6 to IPV4 translation.
Layer 7 HTTP URI load directing is your basic Layer 7 load balancing method.
The “Faster Layer 7 HTTP URI load directing (no compression)” option is the original basic
Layer 7 load balancing feature that was not built with the HTTP compression logic.
Although, both selections will load balance exactly the same way, selecting the “Faster”
method may free up more resources than the normal Layer 7 HTTP URL load directing
option; even if HTTP compression is not being used.
Layer 7 HTTP URL load directing with cookies allows the WebMux to maintain client/server
persistence. This scheduling method also compares the match pattern against the host MIME
header. In other words, a host name can be specified as a match pattern. In order for
client/server persistence to occur, the server will have to generate a cookie first. The
WebMux will generate its own cookie to keep track of which client session belongs to which
server. These are useful for shopping cart services, for example, so that a client will be
directed to the same server and keep their shopping cart items valid. The WebMux cookie
expire time matches the MAX_AGE setting specified in the cookie generated by the servers.
When MAX_AGE is not defined, the cookie expire time is 30 minutes. If the server deletes
the original cookie, the WebMux will also delete its corresponding cookie.
Layer 7 HTTP cookie load directing with cookies tests the match pattern against the cookie
MIME header content only. Client to server persistence is also enabled in this scheduling
method. Lync and Exchange configuration may need to use this option.
Layer 7 HTTP virtual host load directing with cookies allows you to direct traffic to name
based virtual hosts. For other scheduling methods, you cannot put the same server IP address