JSessionID-Based Persistence

Universal Persistence

BIG-IP LTM software includes the Universal Inspection Engine (UIE). The UIE is a set of functions that allows you to direct and persist load-balanced traffic using iRules. Universal persistence uses the UIE which allows you to use persistence for sessions based on content data, or based on connections to a specific pool member, by defining a sequence of bytes in the connection to use as a session identifier.

iRule Example

The following iRule example illustrates how the LTM can find a cookie called FURYNAX in the first response from the server and add a persistence record for that cookie. Subsequent client requests containing the same cookie will persist to the same pool member.

when CLIENT_ACCEPTED {
set add_persist 1
}
when HTTP_RESPONSE {
if { [HTTP::cookie exists "FURYNAX"] and $add_persist } {
persist add uie [HTTP::cookie "FURYNAX"]
set add_persist 0
}
}

when HTTP_REQUEST {
if { [HTTP::cookie exists "FURYNAX"] } {
persist uie [HTTP::cookie "FURYNAX"]
} else {
set jsess [findstr [HTTP::uri] "FURYNAX" 13 ";"]
if { $jsess != "" } {
persist uie $jsess
}
}
}

Another iRules examples

when CLIENT_ACCEPTED {
set add_persist 1
}

when HTTP_RESPONSE {
if { [HTTP::cookie exists "CSPSESSIONID-SP-57772-UP-csp-sys-"] and $add_persist } {
persist add uie [HTTP::cookie "CSPSESSIONID-SP-57772-UP-csp-sys-"]
set add_persist 0
}
}

when HTTP_REQUEST {
if { [HTTP::cookie exists "CSPSESSIONID-SP-57772-UP-csp-sys-"] } {
persist uie [HTTP::cookie "CSPSESSIONID-SP-57772-UP-csp-sys-"]
} else {
set jsess [findstr [HTTP::uri] "CSPSESSIONID-SP-57772-UP-csp-sys-" 34 ";"]
if { $jsess != "" } {
persist uie $jsess
}
}
}

when CLIENT_ACCEPTED {
set add_persist 1
}

when HTTP_RESPONSE {
if { [HTTP::cookie exists "JSESSIONID"] and $add_persist } {
persist add uie [HTTP::cookie "JSESSIONID"]
set add_persist 0
}
}

when HTTP_REQUEST {
if { [HTTP::cookie exists "JSESSIONID"] } {
persist uie [HTTP::cookie "JSESSIONID"]
} else {
set jsess [findstr [HTTP::uri] "JSESSIONID" 11 ";"]
if { $jsess != "" } {
persist uie $jsess
}
}
}

Validate Persistence Records

[root@ltm1:Active] config # b persist show all
PERSISTENT CONNECTIONS --
Mode: universal Value: nVTLLvHDy9GQJQ4T29LPwsLqXXCB2pTGJ3KR49WhpvvBwZyPrxQT!-167612729!-671022569
Virtual: 10.251.3.144:https Node: 10.251.44.2:any Age: 231sec

Mode: source addr Value: 10.21.33.39
Virtual: 10.251.3.145:https Node: 10.251.44.5:any Age: 12sec

Mode: universal Value: Cn18LvHQR8dyZH1S1BmnSxVGcDMvHz12JlTFnJFryvKZpgrrTBdZ!-167612729!-671022569
Virtual: 10.251.3.144:https Node: 10.251.44.2:any Age: 288sec

Mode: universal Value: G4JbLvHXFg2LrXnz71hyJWBGLgT7fQXJbw4G5nhvFThh2pDfymLY!-671022569!-167612729
Virtual: 10.251.3.144:https Node: 10.251.44.2:any Age: 188sec