Local web server intermittent connectivity

[Gyrater]

I am having trouble getting consistent connectivity external to a local web server.
The web server Is locally accessible all of the time.
but externally it runs for about 5 minutes then stops, and I am getting time-out errors on HTTP and HTTPS connections. 

I have used both the DMZ  option and the port forwarding options on the hub 3.0
I have also rebuilt the server on two sets on different hardware. I have tried three hypervisors, and a standard non-hypervisor install. Tried Two different switches and plugged them directly into the hub 3, and 3 different cables. I am running out of ideas. 

The webserver logging doesn't indicate any malicious activity. 

i have tried switching  the hub into modem mode yet, but don't really want to have to run a firewall and AP's 

At this point, I can only think is the traffic is being blocked.

Does anyone have any other ideas or suggestions?

[legacy1]

router mode is buggy for DMZ and port forwarding and VM don't care let alone test but all works fine in modem mode really nothing is stopping you in their eyes.

[Timwilky]

If you are running a web server, perhaps a decent firewall is a must.

I use pfsense for my need, the haproxy service allows me to internet expose multiple devices not just a single server as you currently have, and enforce a wildcard certificate and authentication even when the exposed device only supports http with no authentication.

[Gyrater]

Thanks for the suggestions, built PFense box and put the hub into transparent mode. and its running reliably now.

[Timwilky]

Thanks for the update, Hopefully you have put your web server into a DMZ.

Whilst the easiest route is to simply forward port 80/443 to the server. my personal recommendation would be haproxy on the pfsense.

This would ensure only properly addressed http/s packets ever get to the server. and with the firewall between you have a degree of separation between your web server and the internet.