SBS 2011 - Terrible network performance

[FremontPC]

Good job! It would be nice to know the particulars on that one...

 

[datagnostic]

You're not having duplicate IP's, are you?

Because unless not everything's connected to the switch, there would be no reason for the frames to be sent upstream.

 

[YeOldeStonecat]

So after some more troubleshooting it looks like it is the Ericsson ONT causing the issues.
With that disconnected from the switch I could ping the server from the workstations while transferring test files back and forth without any issues.
As soon as the ONT is connected back in pings to the server start timing out at random times.
I spoke to the ISP who said that they've come across this issue before.
They want me to write a letter to them about the issues so they can take it to the fibre provider (the company that actually installs the fibre and ont to the customers premises)

Glad I got to the bottom of it!

Would love to see this setup, and curious what is allowing this to happen. Shouldn't happen if there's a router in between and only 1x device doing NAT and all network devices are behind the router.

 

[cyabro]

It had me stumped as well as to how just connecting the ONT to the network would cause packet loss to the server and no other devices on the network.
Must be something to do with some port forwarding that's going on as there are a few ports open for remote access and emails.

I checked the server with ProcessExplorer and TCPView to make sure there was nothing going on that I didn't know about and I also tested with an ADSL router, set to the same gateway IP address as the fibre connection, and the issue was not there.