So I recently had an issue with networking on a new droplet. I created the droplet from a snapshot and once it booted, I couldn’t connect to it over SSH. I accessed it over the console through the control panel and confirmed it had no network connection whatsoever. After a little digging I discovered that the network interface configuration was still pointing at the previous droplet’s gateway. I checked the networking page for the new droplet and updated it accordingly, and voila.
However, when trying to diagnose this, I did a little searching (and have done some more since) and I can’t seem to find many people who have had this problem, or had to update this configuration themselves after restoring from snapshot. But it seems like a common operation, in fact, DO themselves have articles on this process themselves (e.g. https://www.digitalocean.com/docs/images/snapshots/how-to/migrate-droplets/) and it doesn’t mention anything about having to update the networking configuration.
So my question is not really why did this happen, I understand what led to it, and it makes sense, I transferred a snapshot which included the old network configuration and so it needed updating. My question is more, how is this not an issue for people constantly, to the extent that DO have to include a note in their help articles on this process? I know I didn’t get unlucky, as all droplets created in that region now seem to use the new gateway, so I’m guessing it’s something that happens every time a subnet fills up; droplets will start being created in the new subnet.
So what gives? How is this not a more common issue? Why is it not easier to diagnose / pre-empt?
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