Right i wanted to put an irule or policy on the VIP on the LTMs to redirect it from the gtm.domain.com name to the datacenter.domain.com name that it's expecting but keep the part of the URL that is wildcarded so that openshift would know where to send it.
DNS record currently *.datacenter.domain.com = VIP on LTM for openshift router with several applications hitting it.
DNS record desired for developers to use = theirapplication.gtm.domain.com
Route currently openshift is configured to recognize = theirapplication.datacenter.domain.com
SteveD1979 Your developers should not be using the FQDN of theirapplication.gtm.example.com they should be using theirapplication.example.com. Please take a moment to look at the two images that explains a little on what is happening when the developers make a query for their app and how DNS should be configured so that the GTM is used appropriately to minimize what the client sees. Pay close attention to what comes back in DNS and what the client uses to make the application request.
I understand that but it would still be the same scenerio. I just wanted to see if it would be possible to rewrite a portion of the URL. If not I'm going to have get our openshift engineer to just add this route. Nothing was settled on yet the URL the devs use could be just application.domain.com but i would still need to flip it to what openshift is expecting as the route
SteveD1979 In order to understand this a bit better could you go into a bit more detailed explanation of Openshift? From what I can tell Openshift has a list of applications and their respective FQDN match. So in this list if they the following I am still failing to see the issue.
If you have to hardcode the destination IP for each app then I can see why you might have an issue but other than that I'm not sure why this is an issue. If I'm incorrect in my assumption please provide some additional detail on how openshift application references function.
The DNS record and the cert for the openshift URL are both wildcarded. so anything that has the *.datacenter.example.com is going to hit the VIP that has the openshift routers behind it. Once it hits the openshift router it sends the traffic to the correct app depending on what is before the .datacenter.example.com in the URL. It's a separate wildcarded DNS based on the datacenter. Openshift is only set up to accept traffic from the routes configured. We're trying to get away from using the specific datacenter in the developers code but also trying not to have to configure a new route inside of openshift.
theirapp1.datacenter.example.com --> resolved to openshift router VIP expecting *.datacenter.example.com --> routes to correct openshift container based on theirapp1
Openshift has to see the .datacenter.example.com to allow the traffic. And all of the applications hit this same VIP.
devs hit GTM theirapp.example.com --> traffic forwarded to appropriate LTM pair in active datacenter that *.datacenter.example.com resolves to --> LTM irule flips theirapp.example.com to theirapp.datacenter.example.com --> traffic goes through to pool member with new URL and openshift expects this host route.
Also obviously i could do this for each individual app but there are many. I wanted to see if there was a way where i could take any request coming in that was in theirapp.example.com and flip it to theirapp.datacenter.example.com
SteveD1979 If this is HTTP traffic you can change it to a standard, apply an HTTP profile, and the irule in question and it should work. If you are doing HTTPS communication it would require that you change it to standard, HTTP profile, SSL client profile, and the iRule and it should work.