LTM v11 iRule Migration

The iRule that they use is not working correctly on v11 or v10.2.3. What happens is when a user clicks on a web page for the first time the iRule runs correctly and the user is presented with the correct webpage in a new window, which is correct. Now if they leave the previous window open and try a different link the iRule runs correctly again.

However, if they close the first window and try a different link the iRule does not run. If you wait approx 60secs and try it again the iRule runs correctly again.

The iRule that they are using I did not create. I know that there are differences for some iRules between versions. I tried looking on F5 knowledge base for the differences and I was unable to locate a difference in the iRule.

So I am just wondering if anyone has run into this issue before? I also am not sure if the iRule is even the problem. So any feed back is appreciate the iRule is posted below.

This iRule parses incoming requests for a particular value in the URI. If present it

will replace the HTTP header and destination IP address with a value retrieved from a

predefined HTTP cookie. It also takes HTTP responses and parses the payload for a

particular string. If present, it will store this value in an HTTP cookie and replace

it with a predefined value.

DevCentral Wiki on HTTP cookie encoding details:

http://devcentral.f5.com/wiki/default.aspx/iRules/HTTP__cookie.html

DevCentral for matching on HTTP payload

http://devcentral-llix.f5.com/Community/GroupDetails/tabid/1082223/asg/50/aft/1397/showtab/groupforums/Default.aspx

DevCentral for selecting pool members based on URL Query

http://devcentral.f5.com/wiki/default.aspx/iRules/Select_pool_member_based_on_HTTP_query_string_parameter.html

DevCentral for using data group list

http://devcentral.f5.com/Community/GroupDetails/tabid/1082223/asg/50/aft/24061/showtab/groupforums/Default.aspx

DevCentral for using stream profiles

http://devcentral.f5.com/Tutorials/TechTips/tabid/63/articleType/ArticleView/articleId/101/LTM-stream-profile-Multiple-replacements-regular-expressions.aspx

http://devcentral.f5.com/wiki/default.aspx/iRules/stream__expression

when HTTP_REQUEST {

Log debug to /var/log/ltm? 1=yes, 0=no.

set debug 0

Disable the stream filter for all requests

STREAM::disable

Set the node and URL to the value contained in the cookie

if {([string tolower [HTTP::uri]] contains "mastermenu") ||

([string tolower [HTTP::uri]] contains "GISOasis/Login.aspx?Logout=true") ||

([string tolower [HTTP::uri]] contains "oasisaccounting") ||

([string tolower [HTTP::uri]] contains "oasisclaims") ||

([string match -nocase {*DRC[0-9][0-9][0-9][0-9][0-9]*} [HTTP::uri]])} {

Set URL original hostname of Oasis Host

set Cookie_URL [string tolower [HTTP::cookie "DRCShared_IP"]]

HTTP::header replace Host $Cookie_URL

Search for value in data group set list matching Oasis Host

set Cookie_Node [class search -value OASIS_LIST equals $Cookie_URL]

if {$debug != 0} {

log local0. "Node $Cookie_Node is being used for $Cookie_URL"

log local0. "[IP::client_addr]:[TCP::client_port]: Debug enabled on [HTTP::method] request for [HTTP::host][HTTP::uri]"

}

node $Cookie_Node 80

}

Prevent the server from sending a compressed response

remove the compression offerings from the client

HTTP::header remove "Accept-Encoding"

Don't allow data to be chunked

if { [HTTP::version] eq "1.1" } {

Force downgrade to HTTP 1.0, but still allow keep-alive connections.

Since 1.1 is keep-alive by default, and 1.0 isn't,

we need make sure the headers reflect the keep-alive status.

Check if this is a keep alive connection

if { [HTTP::header is_keepalive] } {

Replace the connection header value with "Keep-Alive"

HTTP::header replace "Connection" "Keep-Alive"

}

Set server side request version to 1.0

This forces the server to respond without chunking

HTTP::version "1.0"

}

}

when HTTP_RESPONSE {

Trigger collection for up to 1MB of data

Mandatory for buffering data in HTTP_RESPONSE_DATA

if {[HTTP::header exists "Content-Length"] && [HTTP::header "Content-Length"] <= 1048576}{

set content_length [HTTP::header "Content-Length"]

} else {

set content_length 1048576

}

Check if $content_length is not set to 0

if { $content_length > 0} {

HTTP::collect $content_length

}

Check if response is a 404 error code and redirect to gis.grinnellmutual.com if it is

if { [HTTP::status] == "404"} {

HTTP::redirect "https://gis.grinnellmutual.com"

}

Check for redirect and if location URI::host is present and rewrite to gis.grinnellmutual.com

if { [HTTP::is_redirect] && [string length [URI::host [HTTP::header value Location]]] } {

Replace embedded URL to Oasis Host with URL to VIP of gis.grinnellmutual.com

HTTP::header replace Location [string map -nocase "http:// https:// [URI::host [HTTP::header value Location]] gis.grinnellmutual.com" [HTTP::header value Location]]

}

}

when HTTP_RESPONSE_DATA {

Log debug to /var/log/ltm? 1=yes, 0=no.

set debug 0

set found -1

Check for the FQDN of domain oasis.local in the payload

regexp -nocase {GMVM(\d)+\.oasis\.local} [HTTP::payload] found

if {$debug != 0} {

log local0. "[HTTP::payload]"

log local0. "$found is being replaced by gis.grinnellmutual.com"

log local0. "[IP::client_addr]:[TCP::client_port]: Debug enabled" }

if {$found != -1} {

Insert a new cookie with the old host IP name and old cookie's value

HTTP::cookie insert name "DRCShared_IP" value $found domain "grinnellmutual.com" path "/"

Replace embedded URL to Oasis Host with URL to VIP of gis.grinnellmutual.com

STREAM::expression {@http://GMVM(\d)+\.oasis\.local@https://gis.grinnellmutual.com@ @http://gmvm(\d)+\.oasis\.local@https://gis.grinnellmutual.com@}

STREAM::enable

}

}