First of all, be patient, as this is a pretty deep issue, at least for me.
facts:
What am i trying to create?
A multi-functional personal Debian-based (9.4 x64) server with these functions:
1- A Web Server - Using NginX (with active SSL from Let's Encrypt)
2- A personal NAS Server - for local access - Using OpenMediaVault
3- Personal Cloud - Using Nextcloud
What has been done
• The personal NAS is up and running on a 1 Gb/s network, everything is working flawlessly
• The server has been bound to a free domain (from freenom), and is automatically refreshing the DNS (i have a dynamic IP) with a cron job using afraid dns
• Nginx is up and running, correctly serving the welcome page.
• SSH is up and running with certificates and everything
Root of the problem
Where i live, the DPI (Deep Packet Inspection) protocols have been implemented for more than a year now, with the OpenVPN , PPTP and L2TP protocols banned (at least those are the protocols i know for sure are banned)
I spun up a DigitalOcean droplet to duplicate the local server, and check my procedures, and discovered something
I can't ping my local server from the Droplet.
I can't telnet port 80
The only port i can telnet to is port 22 (SSH)
it doesn't matter if i use the ip (assigned at the time) or the domain name
Keep in mind that using my internet connection (Local), my android broadband internet - 4G (Remote), Friend and Family internet (Remote) and pretty much any internet connection in the country, i can do whatever i like to my local server, ping it, telnet to port 80, access the NginX welcome page, do proverbial back-flips , anything i want.
I caught a glimpse of this problem when i tried to use CertBot to get an SSL certificate from Let's Encrypt, and all the methods constantly failed, and when i tried to hit the Let's Encrypt community, several people told me that they cannot ping my server at all, from several different areas around the globe.
This idea solidified when i used the Droplet as Testing ground, indeed it is like my server doesn't even exist.
Sorry for any broken language, and for the lengthy article, but i am currently chasing my imaginary tail, trying to wrap my head around hot this is possible.
Any and all help would be appreciated
