How to divert Rest api calls to a particular node?

[Jonnada Kiran]

Hi I want o divert rest api calls from external applications to a particular node. We are using F5 load balancer. I wrote a irule for this. Can someone certify whether it is correct or not?

rule divertingtraffic{

when HTTP_REQUEST {

if { [HTTP::host] equals"jira.charter.com"} {

if { [HTTP::uri] contains "/rest"} {

{pool/Common/normal}
}

}

if { [HTTP::host] not equals"jira.charter.com"} {

if { [HTTP::uri] equals "/login.jsp"} {

{pool/Common/normal}
}

}

else{
{pool/common/external}

}

}
}

Note: Pool normal contains (JIRA node 1,2,3, 4)

Pool external contains (JIRA node 5)

reference : https://confluence.atlassian.com/enterprise/traffic-distribution-with-atlassian-data-center-895912660.html

[LarryBrock]

Hello @Jonnada Kiran,

It's been a while since I've written irules for F5 but it appears your logic for "/rest" sends it to nodes 1-4 when I'm guessing you want it to go to node 5.  If so, maybe this will work:

rule divertingtraffic{

when HTTP_REQUEST {

if { [HTTP::host] equals"jira.charter.com"} {

if { [HTTP::uri] contains "/rest"} {

{pool/Common/external}
}
}

else{
{pool/common/internal}
}

}

Please forgive the possible syntax errors.  Does this work as you desire?  If so, please remember to accept this answer if it does so others can benefit.

Cheers,
~~Larry Brock

[Jonnada Kiran]

Thanks for the response. I wrote a new irule it works great now.

[Tito_Valentin]

Hi @Jonnada Kiran - do you mind sharing your rule? I'm trying to work out a scenario where any external rest calls go to the rest server. However, if the rest call is from one of the nodes (1 and 2), I need it to stay in that node so that the session auth doesn't break.

For example, I have 3 nodes. 1 and 2 are just web nodes and the third is a rest node. If a user hits jira.domain.tld, the request goes to node 1 or node 2. If a user hits jira.domain.tld/rest/api/2/, the request goes to the rest node. 

Now, if a user is already in node 1 or node 2 and node 1 or node 2 needs to make a rest call, the call then goes out to the rest node and fails with a 401 "unauthorized" because the session is different between node1|2 and the restnode since I have sticky sessions. How can we ensure that rest api requests from node 1 and node 2 stay there instead of sending it out to the rest node to prevent sessions from breaking?

[LarryBrock]

@Tito_Valentin- looks like your question has gone unanswered.  Might try re-asking as a new submission.  Unfortunately, I don't have an F5 I can play with so I won't be able to provide an answer. :-(