Load Balancing JSS, change DNS or change JSS URL?

[hkim]

We're about to flip the switch on a load balancing situation, which is the "best practice"? Change DNS entires on the network so that the load balancer takes the name of the previous master JSS? Or change the JSS URL within JSS itself under Global Management Framework Settings to the current Load Balancer name?

We're trying to do this as seamlessly as possible with clients not re-enrolling into JSS. The first choice I worry about other services that maybe using the original DNS name and breaking (i.e. my distribution point replication scripts), but with the 2nd option I worry about having to re-create new certificates for the new load balancer and things internally with JSS that I'm not aware of breaking when I make that change.

Thoughts?

[jdziat]

Check out the administrators guide, all of these questions are answered there. If you need support contact JAMF they have always been helpful and willing to point me in the right direction when necessary.

[AndyBeaver · Accepted solution]

In our shop we were faced with that very decision. We opted for DNS, having the JSS url resolve to the VIP on the load balancer, and the mysql cluster master (original JSS) changed hostnames and updated DNS. Worked smooth as silk. JAMF support was definitely invaluable though that whole process.

[hkim]

Where in the admin guide does it talk about changing DNS or URL settings for load balancing?

[AndyBeaver]

The admin guide is a little vague on the specifics, I think because there can be so many differences in networks. We used these:
Admin guide 8.7 pages 51-53
https://jamfnation.jamfsoftware.com/article.html?id=305
If you want any more info as to the specifics of how we set ours up, hit me up off board and I would be glad to show you. I would definitely utilize JAMF support in a case such as yours though.

[hkim]

A little vague? =)

What I'd like to know is if on next checkin, the new URL will get pushed down to clients, and if then on subsequent checkin, it'll just use that new URL. I guess what I could do is make the URL change, and then make Extension Attributes to check if the client is checking in through the LB or back to the original master JSS. But I want to know of any other gotchas I might be missing or not thinking about.

[AndyBeaver]

The URL of the JSS in our case never changed, just the dns entry as to where it resolves. Originally when a machine checked in to https://casper.acme.com:8443 it resolved to a Dell server ex, 10.0.1.10 . Now, the machine still knows to check into https://casper.acme.com:8443 but it resolves to the virtual service on the load balancer of ex, 10.0.1.223 with ports 8443 and 8080 open. The load balancer is configured with 3 web apps for the virtual service (real servers ex 10.0.1.218 ,10.0.1.219,10.0.1.220) that work on a least connection.Hope this helps, if any! Sorry for rambling!