Cannot connect to Internet with 20.04

[SumBloke]

Hi folks,
I am trying to conecct using 20.04 which I havent used in a while so it is no doubt out of date.
The connection icon down by the clock says I am connected but I can't connect to the internet or the update servers via the console.
On the console I see "temporary failure resolving 'security.ubuntu.com' and no other info. Ping likewise fails to connect.
I know the ISP connection is fine as other machines are connected using it. The router shows that the ubuntu machine is connected but there is no flickering of the light.
Not much else to go on, does anyone have any ideas please?

[claydoh]

Wired, or Wireless?

Try creating a new connection
if it is wifi, delete the existing one.
Check your clock. You might try setting the time and date manually, if it is incorrect. I have seen this temporarily confuse things before.

[SumBloke]

Thanks very much for the tips!
It is wired connection.
I deleted and re-added a new wired connection, not a shared wired connection although I am using the same connection as other machines that use the same router. Was that correct?
I get the error "Error1 http://ie.archive.ubuntu.com/ubuntu focal InRelease
Temporary failure resolving 'ie.archive.ubuntu.com'
Note that it was http and not https which seems wrong

The time was set correctly.
Thanks for your help

[SumBloke]

Additionally, the connection icon down by the clock, bottom right, shows some activity - a low ammount of download and upload activity.

[kc1di]

Do you know what chip set is being used for the Ethernet? Do you have any firewalls enabled?

[Snowhog]

Please verify: You are able to connect to the Internet; can browse sites with a browser; send/receive email, etc. You just can't update your system 'as expected', yes?

[claydoh]

http://ie.archive.ubuntu.com/ubuntu is empty, and by the date on it, is being auto-generated

It is definitely not empty.
ie.archive.ubuntu.com is just a 'gateway' url that leads to one or more potential mirrors located in that particular country, no different that it does for us.archive.ubuntu.com, or any other country-specific urls.

I deleted and re-added a new wired connection,

I assume you cannot browse the web at all? No proxies or VPNs or anything?

I expect a problem with the Ethernet cable and/or its connection, or something on the router, somehow.

Note that it was http and not https which seems wrong

yes, this is correct. https is for privacy, and with the debian and ubuntu public and volunteer mirror systems, https apparently is not always simple/easy/appropriate worldwide, for the purpose, let alone the scale and number of mirrors Debian and Ubuntu have to keep synced.

gpg keys and package signing and verification prevent 'man-in-the-middle' shenanigans that https would prevent. At this is how i understand it.

of course, https is becoming cheaper and somewhat easier to implement, so at some point I am sure Debian will move to it, eventually, some day, and thus Ubuntu will as well.

[SumBloke]

Please verify: You are able to connect to the Internet; can browse sites with a browser; send/receive email, etc. You just can't update your system 'as expected', yes?

No, I can't connect at all to anything, internet or the update url's

[SumBloke]

Do you know what chip set is being used for the Ethernet? Do you have any firewalls enabled?

The motherboard is MSI with an Intel chipset, using an onboard network card. I have been using a VPN, not sure about the firewall, how can I find that?

[SumBloke]

I can't connect with or without the VPN. I have been using the VPN previously without issues, however I updated it yesterday, perhaps that might be the issue. I also had some old VPN connections from software that i failed to install correctly from another company, so perhps it could be tangled. I removed those connections though by deleting them in the connections list. I guess that software is still installed. (newbie here really!)

[SumBloke]

I expect a problem with the Ethernet cable and/or its connection, or something on the router, somehow.

I'm not sure about that. Router is working for other machines and has worked for this one no problem. Nothering has changed here since the last use, about a year ago!
I suspect a tangle to do with the VPN software which I have just upgraded. As well as the other VPN software mentioned above that I tried and failed to install. Although haveing said that, this VPN has worked ok and it was installed after the failed VPN software I installed. Perhaps there is a clash somehow?

[SumBloke]

I can't connect with or without the VPN. I have been using the VPN previously without issues, however I updated it yesterday, perhaps that might be the issue. I also had some old VPN connections from software that i failed to install correctly from another company, so perhps it could be tangled. I removed those connections though by deleting them in the connections list. I guess that software is still installed. (newbie here really!)

When I say I updated it, I only downloaded and tried to use the latest Appimage. But the connection isnt working with or without that so....

[claydoh]

I'm not sure about that.

A bad cable, or loose connection at the computer or router end. Just something to easily check to eliminate the simple things.

[kc1di]

this page may be of help in diagnosing the problem also.
https://www.linuxandubuntu.com/home/...rk-diagnostics

[SumBloke]

A bad cable, or loose connection at the computer or router end. Just something to easily check to eliminate the simple things.

Yes that is a fair comment. I swapped the cable from a working machine and it's the same problem. The lights on the modem don't flicker at all. The light on the router for this connection flashes once every second or 2 but that is all. It seems as though nothing is reaching the router, so nothing reaches the modem. Gotta be a software/ config tangle no?