I recently changed internet providers, which involved changing my router. Since the switch, I have been unable to connect directly to a (previously working) AWS MySQL database, which I am doing through the terminal on my machine. The specific error is:

ERROR 2005 (HY000): Unknown MySQL server host

I can connect to the database via a hotspot on my phone, so:

  • The connection details I am using are correct
  • The issue is not that my new static IP address needs to be allowed in AWS

Based on this answer it looks like it might be a port forwarding issue? I can set up port forwarding rules in my router (see screengrab), but this doesn't seem to make any difference.

What could be the reason I am unable to connect through my new router and what would be a possible solution?

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1 Answer 1


looks like it might be a port forwarding issue?

Not really. Port forwarding aka reverse NAT aka destination NAT is used for connecting from public Internet to private LAN (for an exposed server/service).

You problem seems to be connecting from a client in private LAN to a server on the public Internet. That requires source NAT/NAPT which most often just works. If everything else does work for you, the most likely problem is a default filter for outgoing connections to TCP port 3306. You need to deactivate that filter or - better - add a rule specifically permitting the connection you require.

For more specific advice we'd need to know the model of the router and its config - note that consumer-grade hardware (your screenshot looks like that) or devices without optional, paid vendor support are explicitly off-topic here though.

  • That's really helpful thanks @Zac67 - I'm a software dev so working this stuff out as I go along. It's a "business" router, but I think it's probably just a consumer router with a different sticker, so I won't go down that rabbit hole. The difficulty I'm having is that I'm able to connect via my mobile, which suggests to me I need to change something on the router itself but the options seem very limited? Commented Oct 10, 2023 at 10:45
  • If it's an ISP router I'd contact them for support. Possibly it's managed by them, leaving few options to you.
    – Zac67
    Commented Oct 10, 2023 at 10:53
  • Thank you - will do Commented Oct 10, 2023 at 12:41

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