I'm having an issue with one user attempting to stream content from a Plex media server. Other external clients can access this host fine and are using the same ports, etc. This is affecting multiple devices on this clients network (2x roku's and a PC) however doesn't affect this client when they are outside this one particular network. This just started happening about 2 weeks ago, before that, all was well for this user.
Everything is pointing to his network/ISP doing something (or not doing something) however I want to confirm I'm not missing anything at the UTM.
I've reviewed rule #1 and I only see firewall traffic from this host saying NAT rule #3 is being obeyed which is consistent with what I would expect as that is the NAT rule that forwards traffic to the internal Plex server.
I ran a packet capture on the Plex server, one from a known good client and one from the affected client. In the affected client's pcap I see retransmissions and not really anything else.
##.##.1.58 = Plex internal IP
##.##.80.19 = Affected client
##.##.20.32 = Working client
Image attached for failing Plex connection (not-working-client.jpg)
Image attached for working Plex connection (working-client.jpg)
Unfortunately this user is remote and not technical so reviewing logs on that side is almost not possible.
From the Plex server logs, it looks like the client never establishes the connection (nothing logged).
One odd (not really) thing is that my public IP address ends in .255 which is normally reserved for broadcast in a /24 network but my ISP is using a /20 network so its a valid address. Could this be causing issues?
What am I missing? Could the UTM be causing the retransmissions or is this squarely on the remote side?
This thread was automatically locked due to age.
