NimbostratusLTM 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
}
}
