Alteon Application Switch Operating System Application Guide
Layer 7 String Handling
804
Document
ID:
RDWR-ALOS-V2900_AG1302
Configuring Regular Expressions
The regular expression feature is applicable to both path strings used for URL-based server load
balancing, and expression strings used for URL-based application redirection.
To configure regular expressions
As a result, both HTTP SLB and application redirection can use regular expression as the resource.
Note:
The more complex the structure of the string, the longer it will take for the server to load
balance the incoming packets.
Content Precedence Lookup
The Layer 7 Precedence Lookup feature enables you to give precedence to one Layer 7 parameter
over another, and selectively decide which parameter should be analyzed first.
You can combine up to two Layer 7 load balancing mechanisms. You can specify which types of Layer
7 content to examine, the order in which they are examined, and a logical operator (and/or) for their
evaluation.
The following Layer 7 content types can be specified:
•
URL SLB
•
HTTP Host
•
Cookie
•
Browsers (user agent)
•
URL hash
•
Header hash
Using these content types with the and and or operators, Alteon is configured to refine HTTP-based
server load-balancing multiple times on a single client HTTP request in order to bind it to an
appropriate server. Typically, when you combine two content types with an operator (and/or), URL
hash and header hash are used in combination with host, cookie, or browser content types.
For example, the following types of load balancing can be configured:
•
Virtual host and/or URL-based load balancing
•
Cookie persistence and URL-based load balancing
•
Cookie load balancing and/or URL-based load balancing
•
Cookie persistence and HTTP SLB together in the same service
•
Multiple HTTP SLB process type on the same service
Note:
Cookie persistence can also be combined with the Layer 7 content types. For more
information on cookie persistence, see
>> # /cfg/slb/layer7/slb/addstr
