Brocade Virtual ADX Server Load Balancing Guide (Supporting ADX v03.1.00) - Manual (Page 294)

278 Brocade Virtual ADX Server Load Balancing Guide
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Server passive cookie persistence
5
Once the offset point is set by the persistence-string-offset, the system will parse the search-string
variable matched in the specified CSW rule up-to the number of characters defined by the value of
the persistence-string-length variable. The value of the persistence-string-length variable must be
greater than 0 (zero). If the value of the length variable extends beyond the length of the
search-string variable, the system will look to the end of the string to define the string used for
hashing.
For example: if the search string is “JSESSIONID” and the offset is “0”, the string will be parsed
beginning with the “=”. If the persistence-string-length variable is set to “7”, the string used will be
“0123456”.
Specifying a CSW action to perform persistence lookup and retrieve real server
information
To specify a CSW action to perform persistency information lookup and use stored real server
information to forward requests, use the following command.
Virtual ADX(config)#csw-policy p1
Virtual ADX(config-csw-policy-p1)#match r2 persist offset 0 length 11
passive-persist
Syntax: [no] match rule-name persist offset persistence-string-offset length
persistence-string-length passive-persist
The rule-name variable is the name of a previously configured CSW rule that was defined to match
a client request.
The persistence-string-offset variable specifies the number of characters that will be skipped after
the start point of the search-string matched in the specified CSW rule. Normally this value is 0
(zero) which places the start point at the beginning of the string. For example: if the search string is
“JSESSIONID” as specified in r1, and the offset is “0”, the string will be parsed beginning with the
capital “J” in “JSESSIONID.” If the offset is “7” the string will be parsed beginning with the capital
“N”.
Once the offset point is set by the persistence-string-offset, the system will parse the search-string
matched in the specified CSW rule up-to the number of characters defined by the value of the
persistence-string-length variable. The value of the persistence-string-length variable must be
greater than 0 (zero). If the value of the length variable extends beyond the length of the
search-string, the system will look to the end of the string to define the string used for hashing. For
example: if the search string is “JSESSIONID” as specified in r1, and the offset is “0”, the string will
be parsed beginning with the capital “J” in “JSESSIONID”. If the persistence-string-length is set to
“7”, the string used will be “JSESSIO”.
Example
The following example is similar to the example shown in Figure 32 with the following operation:
1. The Client request the following URL: www.test.com
2. The server responds with a page and performs “Set-Cookie: PSrvrID=1234567”
The page contains several URL such as: href=”test/nextpage.html?PSrvrID=1234567"