Remote Access Suddenly Stopped

[fountain27]

Over the weekend my remote access suddenly stopped working. I was experiencing some network issues and decided to reboot the network. I then noticed I lost remote access which has happened in the past. Normally I can get my home external IP Address, login and update DuckDNS with the new IP Address. However, this time is different.

I cannot even access the server with the external IP Address / Port 5001. The odd part is I can remote access my Rasberry Pi on the same network running Home Assistant using the same IP address with just a different port #. I have double-checked my router to ensure the port is open. I have rebooted the server a few different times, deleted my DuckDNS credentials in DSM, disconnected my VPN on the server, but still no luck. The LAN access is working just fine.

I sincerely appreciate any advice.

 

[fountain27]

After a few days of trial and error, I decided to create 2 new DDNS's using both DuckDNS and Synology. I was able to get both to connect in the Remote Access section of the Control Panel. I was able to access the server from my home network using both of the newly created DDNS's.

However, now trying from my office both of the DDNS's fail to connect. All appropriate ports are open on my router and I can still remote access my Raspberry Pi running Home Assistant.

I sincerely appreciate anyone's advice.

 

[fredbert]

I'm not clear exactly what your are doing. When you say 'remote access' do you just mean connecting to the NAS from the Internet using port forwarding rules in your Internet router/firewall? Or are you using VPN Server to create an OpenVPN or L2TP/IPsec secure tunnel to the NAS?

Have you assigned a static LAN IP to the NAS? Usually this will be a feature of your router.

 

[fountain27]

Sorry if I misused a term or phrase. Networking is not my strong suit.

Yes, connection to the NAS remotely using an internet connection. Synology's Description.

I have assigned a static IP Address on my router for the NAS.

 

[fredbert]

OK. I was aware that Synology use 'external access', which says exactly what it is, but hadn't seen they interchangeably use 'remote access'.

If you've set up DDNS and that is maintaining the associated IP to be that of your ISP WAN IP then things should work when you create the port forwarding rules in the router. The other thing would be to check if you are using secure connections and that the SSL certificate you've assigned on the NAS will cover the server names you're requesting to access: many web browsers report issues if there is an issue with a server's certificate and will stop access, or require you to approve a bypass.

One more thing: many businesses will restrict the destination ports and applications that the internal users can access. A simple example that many will restrict users to access only HTTP (TCP port 80) and HTTPS (TCP port 443), maybe a few other business related ports. With application and cloud service awareness then business may then open specific access to business apps that provided in public cloud services (M365 etc), how will depend on the organisation's size and depth of pocket.

So you may have an issue from work if there is a firewall blocking the ports you forward to the NAS. If this is a problem then you can use the NAS's Login Portal features to setup up unique server names for your packages, which will use the built-in reverse proxy to receive all TCP 443 (HTTPS) traffic and direct the requests to the correct package.