Wednesday, February 14, 2018

Don't forget your firewall settings

I've been working with migrating and discussion forum application into Azure over the past few months and yesterday ran into a perplexing issue when working from my computer on my home network. Using the .Net client library I was trying to connect to my database and kept receiving the error

Entity with the specified id does not exist in the system.

Which was most perplexing as it was all working fine earlier and I could browse the data via the Azure Portal. After much wailing and gnashing of teeth, I remembered that I had set the firewall on the CosmosDB to only allow Azure services and my work IP address (if you don't meet the IP address the REST call receives a 404 hence the 'does not exist' phrase in the error message). Adding my home address and waiting a few minutes soon meant that I was on my way.

So if you are getting this error and wandering why a database or collection that you know exists is returning this error, check your firewall ;)