NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.

Forum Discussion

bho45666's avatar
bho45666
Aspirant
Nov 19, 2021

Orbi port forwarding not working

Hi,    I am trying to set up port forwarding on my Orbi AX4200. The purpose is to set up remote access to my Plex server running on a Synology NAS, which is connected to one of the satellites of my...
CrimpOn's avatar
CrimpOn
Guru - Experienced User
Feb 25, 2022
Aggie94 wrote:

The reason you change the external port is because I have two plex servers in my home (for different reasons like transcoding ability).  One on a pc running unraid and another on the synology nas. 

Thanks.  That makes perfect sense. So, both Plex servers are reachable from the internet using the Plex Media app, but canyouseeme does not show the port open.  Very interesting question.

 

Would it be convenient to try a few other web test sites?  Gibson Research "SheidsUp!", for example. https://www.grc.com/shieldsup 

 

It could have something to do with the method the Plex server uses to connect.  I don't know if this question is worth a lot of your time (since both Plex servers are working).  Maybe Plex only accepts a connection that contains specific information?  My approach would be to use the Orbi debug capability of "Enable LAN/WAN Packet Capture".  Begin the capture, then try some "can you see me" web sites. Then connect using the Plex Media app.  Save the debug file to your PC and then use Wireshark (or a similar pcap utility) to open both the LAN.pcap and WAN.pcap files.

 

The LAN capture will be the easiest because Wireshark can use a display filter to show only the packets going to/from the media server(s).  (ip.addr == 192.168.1.11)  What I suspect might happen is that there will be TCP packets going from the Orbi router to the Synology, but no responses going back to the router.  Then, when Plex Media connects, there will packets going to the Synology and packets going back to the router (the router being the gateway to the internet).

 

The WAN side will be more difficult because all incomming packets are addressed to the Orbi router and Network Address Translation hides the internal IP address.

Aggie94's avatar
Aggie94
Aspirant
Feb 25, 2022

the shieldsup is green for port 32605 to my NAS port forward.   it didn't say open, rather stealth.   on a whim, I disabled the firewall on the nas for a few seconds and it passed.  so, the issue is not the netgear router and I'm sorry if I mucked up this guys thread.  thanks for all the help. 

  • CrimpOn's avatar
    CrimpOn
    Guru - Experienced User
    Feb 25, 2022
    Aggie94 wrote:

    the shieldsup is green for port 32605 to my NAS port forward.   it didn't say open, rather stealth. 

    Thanks for taking the time for this other test.  SheldsUp! defines a port as

    • Open - when a connection attempt is accepted
    • Stealth - when the connection request just 'disappears'. No response of any kind.
    • Closed - when a port responds to the connection request with a denial.

    There is an interesting discussion in the FAQ about why Gibson uses the terms he does when other sites use other terms.

     

    Not having much luck finding a reference for the Plex client/server TCP handshake.

    This post says it is an http header:

    https://www.reddit.com/r/PleX/comments/g7yge1/how_does_plex_serverclient_handshake_work/