Setup: Intel NUC 8GB 240gb M.2 Drive, Linux Mint 19.1
Tested NUC connected on the Local Customer Server Network - OK (Network 1gb Unmanaged Switch)

Installed at Customer Branch network will not RDP (Remmina) to File Server.
Laptop (Windows RDP) on same network wall socket work correctly
Existing PC / Thin Clients / Laptops working correctly.

Remote to Intel NUC using Simplehelp worked intermittiently; reconnecting after 10 to 40 or 80 seconds.
Connect NUC to WiFi Intel NUC working perfectly.
What am I missing ?
(Network 1gb Unmanaged Switch)
If you are able to assist please give the instructions to fix.

Thank you for reading this.
Terry

I suspect that the answer is yes, but just to be precise, are you using the same ethernet cable with both machines?

Tks frankbell,

Using CAT5e cable unit to wall. All cabling both sites is Cat5e Spec.
Have changed cables unit to wall and repatched the switch input.

Rgds
Terry

While it could be a hardware problem, what is different between the local and branch server networks? How did you configure the ethernet adapter?
Maybe an IP conflict but could be some other configuration problem. Does the NUC still work ok if you connect it back on the local network?

Do you have access to another network port at which you can test the ethernet connection with a known-good cable, ideally on a different network? Heck, even a home router would do.

Hi Frank,
Tks for coming back.
Server site is on an HP 40 port unmanaged switch CAT 5e cabling; also tested on my workbench SOHO router; access internally and externally worked.

Remote site HP 24 port unmanaged switch (brand new - swopped old one out thought it could be the issue) CAT5e cabling.
Mint Network setup left at default for all testing and operating site.
The NUC has been moved around the office, different wall sockets, therefore different switch ports and cables.
Agree it is definitely site related as this is the second Intel NUC sent to this site that will only work on WiFi. but trying to get to the issue is perplexing.
I have these units in two other remote site for this company and they "just work" with default setups.

I originally posted on the Mint site and someone came back and asked me to run Post output of terminal command; inxi -Fxz, and post back, I did but he has "gone dark".

The Results were as follows, but this seems to only be a hardware analysis....
"Site_Name"-nuc-reception@"Site_Name"-Bris-Reception:~$ inxi -Fxz
System:
Host: "Site_Name"-Bris-Reception Kernel: 4.15.0-47-generic x86_64 bits: 64
compiler: gcc v: 7.3.0 Desktop: Cinnamon 4.0.10
Distro: Linux Mint 19.1 Tessa base: Ubuntu 18.04 bionic
Machine:
Type: Desktop System: Intel Client Systems product: NUC8i3BEK
v: J72748-303 serial: <filter>
Mobo: Intel model: NUC8BEB v: J72693-304 serial: <filter> UEFI: Intel
v: BECFL357.86A.0051.2018.1015.1513 date: 10/15/2018
CPU:
Topology: Dual Core model: Intel Core i3-8109U bits: 64 type: MT MCP
arch: Kaby Lake rev: A L2 cache: 4096 KiB
flags: lm nx pae sse sse2 sse3 sse4_1 sse4_2 ssse3 vmx bogomips: 24000
Speed: 600 MHz min/max: 400/3600 MHz Core speeds (MHz): 1: 600 2: 600
3: 600 4: 600
Graphics:
Device-1: Intel driver: i915 v: kernel bus ID: 00:02.0
Display: x11 server: X.Org 1.19.6 driver: modesetting unloaded: fbdev,vesa
resolution: 1920x1080~60Hz
OpenGL: renderer: Mesa DRI Intel HD Graphics (Coffeelake 3x8 GT3)
v: 4.5 Mesa 18.2.8 direct render: Yes
Audio:
Device-1: Intel driver: snd_hda_intel v: kernel bus ID: 00:1f.3
Sound Server: ALSA v: k4.15.0-47-generic
Network:
Device-1: Intel driver: iwlwifi v: kernel port: 4000 bus ID: 00:14.3
IF: wlp0s20f3 state: up mac: <filter>
Device-2: Intel Ethernet I219-V driver: e1000e v: 3.2.6-k port: efa0
bus ID: 00:1f.6
IF: eno1 state: down mac: <filter>
Drives:
Local Storage: total: 119.25 GiB used: 8.34 GiB (7.0%)
ID-1: /dev/sda vendor: Kingston model: SM2280S3120G size: 111.79 GiB
ID-2: /dev/sdb type: USB vendor: SanDisk model: Cruzer Switch
size: 7.45 GiB
Partition:
ID-1: / size: 109.04 GiB used: 8.34 GiB (7.6%) fs: ext4 dev: /dev/sda2
Sensors:
System Temperatures: cpu: 38.0 C mobo: 27.8 C
Fan Speeds (RPM): N/A
Info:
Processes: 199 Uptime: 5h 29m Memory: 7.66 GiB used: 898.6 MiB (11.5%)
Init: systemd runlevel: 5 Compilers: gcc: 7.3.0 Shell: bash v: 4.4.19
inxi: 3.0.27
"Site_Name"-nuc-reception@"Site_Name"-Bris-Reception:~$

Thank you for any assistance

Terry

Hi MichaelK

Tks for coming back ..
Some of your questions I replied to in the above comment to Frank.
As suggested I'll get it back on the local network and RDP to another PC then RDP to the NUC and see what happens.

Tks
Terry

I went back and looked at your first post. Are you saying that the ethernet worked at the first location [Tested NUC connected on the Local Customer Server Network - OK (Network 1gb Unmanaged Switch] but not at the second (it's intended location)?

If that is the case, then either wall socket port or the network at the second location is wonky or something went wrong with the NUC's hardware ethernet port in transit. I really can't see any other options. It's a really long shot, but can you pop the case open and eyeball the wiring to the port?

In addition to the above did you run the inxi command when the NUC was wired into an ethernet port?

Hi Frank,

Yes, Ive always thought it may be cabling, on remote site, but when PC's / Laptops / HP Thin Clients work correctly off the sockets the NUC wont; then this does cloud the synopsis.

NUC worked over ethernet when tested from my workshop; RDP'd to the clients H.O. and to a number of over clients and ran their local applications - all worked correctly.
NUC Worked at First location (H.O.) as ethernet connect, to unmanaged Switch.
Remote site ethernet wont connect solidly to its unmanaged switch. Runs for 20 - 80 secs then RDP attempts to reconnect.
Wifi has been solid.

Tonights move is to be:

Client on the Remote site, is plugging NUC into the Network switch, using "out of the packet" network cable.
a. I will attempt to connect to the NUC remotely using Simplehelp
b. Will attempt to RDP to the NUC from a local PC on the Remote site
c. will attempt to RDP to the NUC from the H.O. Server

This will eliminate cabling / wall sockets / fly leeds.

I'll someone to check the NUC, but this is the second NUC sent to site, to exhibit the same problems.
When first NUC was sent back works correctly on client site and off my workbench.

See what tonights test turn up.

Also I am relying on people onsite to perform as directed.

Just now eliminated one concern, they have 2 outlets per desk; rechecked they were in the correct outlet - yes they are.

I'll test tonight and come back

Thanks

Terry

Hi Michael,

No only tested on Wifi, will run on ethernet; if I can get it running tonight.

Thanks
Terry

Hi Frank / Michael,

The NUC was directly into the switch, couldnt access it remotely
Dumbo user turned off local PC to test local RDP - will try again tonight.

Have asked ISP for config dumps of their managed Cisco routers to see if there are any differences that may be the cause of the issues - Yip real long shot ..

Thanks
Terry

I have retried with the NUC on the Ethernet cabling.
a. Very intermittent access externally. Would connect stay up for about 10 40 sec then disconnect.
b. Very intermittent access internally. Would connect stay up for about 10 40 sec then disconnect.

Obviously not been able to be onsite, due to distance (900+km) doesn't help.
Have had local contractors onsite can't find anything untoward.

Still waiting for the ISP's Cisco dumps.

Tks
Terry