When internet goes down network goes down

[foxint]

Hi Guys,

I do not understand.

I still cannot talk with the PC's when the internet is down.

What is my problem?

What do I have to check? The OPN box or my network settings?

How do I find cookiemosters #9 post? What do I need to check?

Thanks
Dan

[cookiemonster]

No problem. Here it is again:

@foxint - Please tell what are your DNS settings, so to rule them out.
a) Systems | Settings | General.
b) Unbound or dnsmasq - which do you have enabled, share the settings.
c) On your LAN interface settings. Share those too please.

So for a), you log onto your OPN User Interface and navigate from the left. Click on "System" on the vertical left menu, then that opens on the right when clicked. There you expand still on the left the "Settings" and then again in "General".
We are interested in what settings you have there. Specifically those for DNS.
What I want to see is what DNS settings you have set there.
Then similar for b) you need to tell us which service you have enabled and with which settings.
Finally c).
It is not unusual for DNS settings for the network to be incorrect to cause what you describe. Your network clients are relying on DNS to function but that said, I'm a little unsure now we have other basics cleared.

Can you please explain what you mean you can not talk with the PCs, how do you try? And does is still happen when the internet is down (which I think you said is not a problem anymore?)

[foxint]

Thanks

DNS servers
1.1.1.1
8.8.8.8

Unbound or dmsmasq – I do not know what these are or where to find them.

Lan interface - I do not know what these are or where to find them.

"Cannot talk with the Pc's". when the internet goes down/stops, I cannot access the other PC's on the network.

The network is OK when I remove the internet. So the problem remains when I re-insert the internet.

Thanks
Dan

[passeri]

I cannot access the other PC's on the network

@foxint, what do you mean by this please? Are your other PCs acting as servers, or you mean you cannot use things like mail or social pages between them? How are you "accessing" other PCs?

Does Opnsense show the IP addresses of all machines when you disconnect WAN (/Interfaces/Diagnostics/ARP table in the menus on the left)?

[foxint]

Hi

Thanks for asking.

I have 1 PC with a programme that I access from my main PC and the other PC's act as storage and back up for my data.

I usually access the PC's using Windows Explorer, Tight VNC (and more recently trying to make Remote desktop to work – but that is a challenge). Also, I have a synchronisation programme that "should" automatically synchronise the data (but that is also having issues).

"Does Opnsense show the IP addresses of all machines when you disconnect WAN (/Interfaces/Diagnostics/ARP table in the menus on the left)?"- I have no idea.

Thanks
Dan

[passeri]

Thank you for your answers. I understand the problem better. I suspect that the DNS trail others are following will prove to be the issue.

"Does Opnsense show the IP addresses of all machines when you disconnect WAN (/Interfaces/Diagnostics/ARP table in the menus on the left)?"- I have no idea.

In OPNsense menus, if you follow the trail I gave you (/Interfaces/Diagnostics/ARP table) then you will see a list of recognised devices with their IP addresses (which you can ignore). If the number of devices listed approximates the number of devices you think you have, or you recognise device names, then Opnsense is not blocking their communication just because the internet is down.

To check Unbound or DNSmasq as cookiemonster requested, go to each of the menus /Services/DNSmasq DNS/Settings and /Services/Unbound/General. In each case, there will be a box at the top for "Enable". Is either one ticked?

[cookiemonster]

Thanks

DNS servers
1.1.1.1
8.8.8.8

Unbound or dmsmasq – I do not know what these are or where to find them.

Lan interface - I do not know what these are or where to find them.

"Cannot talk with the Pc's". when the internet goes down/stops, I cannot access the other PC's on the network.

The network is OK when I remove the internet. So the problem remains when I re-insert the internet.

Thanks
Dan

You are going to have to get down and dirty a little with your new box Dan, no escape. You installed it I presume, so please revise the installation instructions https://docs.opnsense.org/setup.html . You'll get help but go over those basics please. it'll get us faster to the solution.

let's go back a little:

I have a LAN comprising of 5 PC's all with static IP addresses. When I am using the internet and it stops and pauses – that it does all the time, I cannot access any of my PCs on the LAN. I use programmes that must connect to the internet to function, and I access this via my workstation on another PC on the network. (This arrangement is the preferred arrangement from the software vendor – MYOB. It is a real princess of a programme and as such I had to buy a completely new PC as it does not like sharing).

Static IP addresses could be a problem if you just insert a new network router. Where are the static ip's set, on the devices themselves? Describe it please. How are your machines connected to each other, a switch? where does it connect to OPN? Please describe the layout. We're interested in ports and the setup of those ports. In a router (OPN in this case) they become "Interfaces".

Connection: Internet modem to OPNsense box – OPN to switch – all PC's to switch via ethernet.

Internet goes down – I cannot get anything from the internet. The internet indicator (Win 10) on the task bar says no internet.

When I take OPN box out of the system the network operates. When it is in the system and the internet goes down, I cannot access my PC's on the network.

This is along the way what we need. Are you sure your modem is not also a router, otherwise you could be double NATing and might be part of the problem. How to check? Well we don't know your hardware so you'll need to find out a bit from your ISP or their forums, or their documentation (online I hope). If you can't tell, give us the url of your ISP, modem model and we'll see if we can ascertain it for you.

When "the internet goes down", could it be that actually your ISP has a problem, or that the modem is going offline? No much use looking in OPN for that. How to tell? Diagnostics by methodical elimination.
That said, when that happens, your machines connected to the switch should also be affected (no internet, so no access/connectivity to the outside) BUT they should be able to connect to each other. But here is the thing. They can only connect to each other by IP address (for simplicity, local name resolution we'll park for now). So you need to be able to diagnose that. Do you know how to connect by IP ? You mention windows explorer and I don't know much Windows but I imagine you can enter the IP in it to the machine you want to connect to. Otherwise a ping command from the command line.

[foxint]

Hi

I am glad you understand, I do not.

See attached. It has my PC's on the list.

""To check Unbound or DNSmasq as cookiemonster requested, go to each of the menus /Services/DNSmasq DNS/Settings and /Services/Unbound/General. In each case, there will be a box at the top for "Enable". Is either one ticked?

I could only get to "setting" – not sure where Services/Unbound/General is? But on my screen in General enabled is NOT ticked – should be it be ticked?

Thanks
Dan

[cookiemonster]

I could only get to "setting" – not sure where Services/Unbound/General is? But on my screen in General enabled is NOT ticked – should be it be ticked?

It's the one called "Unbound DNS". Sorry, I should have been clearer. What's there? You are spot on, is it ticked.

[passeri]

/Services/Unbound/General

From the top level of the menu, Services, Unbound, General.

You have already found DNSmasq under Services, so it is the same routine.

[foxint]

Quick question - ticked or NOT ticked for them both?

[foxint]

Hi Cookiemonster.

Thank you.

I have set up static IP Addresses on each PC on the PC. I have connected the PC's to dumb switches.

The OPN box has a cord to one of the switches.

As far as I am aware the modem only deals with the internet. There is one cord to the wall and the other goes into the OPN box.

I have no hardware from my ISP. The modem box is provided by the NBN (National Broadband Network) people. I am not sure what is should be called we call it the NBN Box. I have fibre to the curb.

I have the NBN box ----- OPN Box ---- Switch.

I have been dealing with the continual dropouts with my ISP. The only thing the ISP refuses to do is test the NBN Box, because the NBN people deny any service failures.

Regardless of who is to blame (we have a very Donald Ducked system here), I get internet dropouts and then my network goes down.

I just tried to enter the IP Address of one of my PC's and it timed out. They all timed out.

Thank you.

Dan
PS – Thanks for the link to the set up (https://docs.opnsense.org/manual/interfaces.html). I do not understand any of this. I got lost at Virtual Machine, Trust Certificates, Change logs 2FA TOTP..... It was hard enough getting the programme onto a USB stick. I appreciate it is a great programme, but I have no idea its full capabilities, or what I should have or what I want.

[cookiemonster]

Can you please show the settings on Interfaces | LAN. We're going to have to focus on device to device connectivity.

[foxint]

Thanks.

Interfaces/LAN - I think. See attched.

[foxint]

Photos