Integrating DNS between Oracle Cloud and Oracle Cloud VMware Solution.
If in doubt, you blame the Firewall. But, if you know your stuff, and particularly if you manage a firewall, you’ll know that the real culprit is always DNS… Yes, DNS is often the villain of the piece. Seeming to be innocently minding its own business, until it does that thing it does when it doesn’t do what you think it should! Something you typically discover after hours of exasperated hair-pulling and teeth gnashing. In the interests of restoring some balance, here’s a short post exploring how we can get the best out of DNS within an OCI/OCVS environment.
In the last exciting instalment, we saw our heroes bravely reaching out to explore the Internet! But what if the Internet wants to come visit us? Or in slightly less Sci-Fi movie language, we want to publish services from OCVS out to the Internet? Well, we have a bunch of the parts already assembled, but we’ll need to change some, scale some, and do even more NAT! Read on for the conclusion next instalment* of our gripping story…
Okay, so we have our Oracle Cloud VMware Solution (OCVS) up and running, we can connect to the vCenter, NSX Manager etc. and have started to deploy workloads inside the SDDC, that’s awesome! But, now we want to be able to connect to the Internet from those workloads, and, just maybe, connect to them from the Internet. In this post, we’ll look at the steps needed to enable our workload VMs to access the Internet. Then, in the second post in this series, we’ll err… break that, hurriedly fix it (while hoping nobody noticed it was us), and enhance the Internet access to allow us to publish services to the Internet from the SDDC.
As a first class citizen of Oracle Cloud Infrastructure, the network layers of the Oracle Cloud VMware Solution are interlinked with those of the parent OCI Virtual Cloud Network (VCN). Understanding how the networks of each layer relate to each other is important, but difficult to visualize, so, to help with that, here’s a Reference Architecture poster.
Because Oracle Cloud VMware Solution (OCVS) is a fully customer-managed implementation of the VMware Cloud Foundation stack, hosted on Oracle’s global Cloud Infrastructure platform, it’s arguably the Hyperscaler VMware offering which is most like your existing on-premises deployment. However, unless your on-prem deployment is on an “OCI Dedicated Region Cloud @ Customer” it’s unlikely that your network underlay is quite the same as the one underpinning OCVS. In this post we’ll see one of the ways this shows up, and how you can work around it.