topic Re: net::err_ssl_protocol_error in Network Platform API

net::err_ssl_protocol_error

gatta — Mon, 24 Apr 2023 11:13:49 GMT

Hello there,

We have a client + server web platform,

The two entities communicate via http in local and the tests in local pass without problem

Now the client part is hosted on the internet and must send requests to the server which is hosted locally

We have done a port forwarding on our appliance but we have a problem establishing a SSL connection between the remote site and the appliance

Can anyone help us?

Re: net::err_ssl_protocol_error

GreenMan — Mon, 24 Apr 2023 15:42:03 GMT

If you're thinking this is something with your MX, you should look to post to the SECURITY / SD-WAN Forum.

Did you take and examine some packet captures on the WAN / LAN interfaces of the MX, to see whats going on? If you haven't already, I'd raise a case with Meraki Support too

Re: net::err_ssl_protocol_error

janki-p12 — Thu, 11 Sep 2025 10:27:37 GMT

I had the same issue with net::ERR_SSL_PROTOCOL_ERROR when moving from local HTTP tests to a client hosted online. The error usually comes up because the remote client is trying to connect over HTTPS, but the local server doesn’t have a valid SSL certificate or isn’t configured properly. Make sure the forwarded port points to the right service and that the server has a trusted SSL cert (self-signed often fails on browsers). You may need to install a valid certificate from a CA and check TLS version support. Once I added a proper cert and adjusted the appliance forwarding, the SSL connection worked fine. Hope it helps!