How to remove a damaged Wired Connection

Sun Aug 28 15:43:11 UTC 2016

At Sun, 28 Aug 2016 17:22:56 +0200 irons.charles at gmail.com wrote:

> 
> 
> 
> On Sun, 2016-08-28 at 09:40 -0400, Robert Heller wrote:
> > At Sun, 28 Aug 2016 15:18:15 +0200 irons.charles at gmail.com, "Ubuntu
> > user technical support,  not for general discussions" 
> > ists.ubuntu.com> wrote:
> > 
> > > 
> > > 
> > > 
> > > 
> > > Hello all. I hope you can help.
> > > My terminal command skills are limited as a retired end user of
> > > Ubuntu
> > > (since 05.04).
> > > 
> > > My Settings/Network shows two Wired entries (because my ADSL
> > > service
> > > was poor so my ISP gave me a wireless router that works) but my
> > > browser
> > > will not connect if the router is switched on first.
> I assume that is why I must start my desktop first, then start the
> router.
> > > 
> > > The lower Wired entry for the eth0 DSL router shows "Cable unplugged"
> > > because it was replaced by the eth1 wireless router.
> > > Settings/Network/Options for the eth0 Wired entry shows "Error Editing
> > > connection: Did not find a connection with UUID '(null)'"
> > > because I did "delete" but it still appears. I cannot find a way to
> > > remove this entry in Ubuntu users guide.
> > > 
> 
> > 
> > 
> > Unless this is a desktop machine with a PCI (removable) Ethernet card that you
> > can remove (ie it is a *really old* computer), you cannot 'remove it' -- so
> > long as the NIC shows up in your hardware scan at boot time, it will be there,
> > maybe not configured or not connected ("Cable unplugged"), but still there.
> > You can *edit* it, assuming you ever find a reason to plug in an Ethernet
> > cable from the RJ45 jack on your computer to anther LAN at some point. Why do
> > you want to remove it? Is this some silly 'neat and tidyness' thing?
> > 
> 
> Yes my desktop has an ethernet card where the ADSL router was
> connected. Maybe that will be used again when fibre-optic cabling is
> installed here in a month or two?

Possibly.  Depends on what sort of ONT (Optical Network Terminator) is 
installed.  Some are 'wired' and some are 'wireless'.

> Now that you have explained it, I will ignore the Wired entry for eth0
> but I still wonder if it blocks eth1 from starting.

It shouldn't.  Note that there might be other issues.  What does 
/etc/network/interfaces look like?

> You see that I still miss some basic network concepts. Thanks for
> helping.
> > > 
> > > 
> > > The upper Wired entry is working (TIAllAccess wireless eth1)
> > > When I click on Menu bar/Edit Connections it shows only one Ethernet
> > > router (TIAllAccess wireless eth1).
> > > Then I click on Menu bar/Edit Connections/Edit TIAllAccess and it shows
> > > the MAC details of the router (eth1).
> > > After I click on Menu bar/Connection Information it shows details of
> > > the router (eth1).
> > > 
> > > Please tell me how to remove the second Wired Connection. 
> > > Maybe that will allow my browsers to connect to eth1 (the TIAllAccess
> > > wireless) when it is already running; it does not switch off and on
> > > again easily.
> > > 
> > > Maybe the Syslog snippets below will help? (that I found when I scanned
> > > there for some details)
> > > 
> > > *********
> > > devices added (path:
> > > /sys/devices/pci0000:00/0000:00:1c.2/0000:03:00.0/net/eth0, iface:
> > > eth0)
> > > Aug 28 11:54:26 Charles-PC NetworkManager[2350]:
> > > <info>  [1472378066.2036] device added (path:
> > > /sys/devices/pci0000:00/0000:00:1c.2/0000:03:00.0/net/eth0, iface:
> > > eth0): no ifupdown configuration found.
> > > ********
> > > Aug 28 11:54:26 Charles-PC NetworkManager[2350]:
> > > <info>  [1472378066.2036] settings: loaded plugin ifupdown: (C) 2008
> > > Canonical Ltd.  To report bugs please use the NetworkManager mailing
> > > list. (/usr/lib/x86_64-linux-gnu/NetworkManager/libnm-settings-plugin-
> > > ifupdown.so)
> > > ***********
> > > keyfile: new connection /etc/NetworkManager/system-connections/Wi-Fi
> > > connection 2 (83c73dc1-d951-4d72-a919-13631ee95fca,"Wi-Fi 2")
> > > ********
> > > NetworkManager[2350]: <info>  [1472378067.5006] manager: (eth0): new
> > > Ethernet device (/org/freedesktop/NetworkManager/Devices/1)
> > > Aug 28 11:54:27 Charles-PC NetworkManager[2350]:
> > > <info>  [1472378067.5012] device (eth0): state change: unmanaged ->
> > > unavailable (reason 'managed') [10 20 2]
> > > Aug 28 11:54:27 Charles-PC kernel: [   25.609959] IPv6:
> > > ADDRCONF(NETDEV_UP): eth0: link is not ready
> > > Aug 28 11:54:27 Charles-PC NetworkManager[2350]:
> > > nm_device_get_device_type: assertion 'NM_IS_DEVICE (self)' failed
> > > Aug 28 11:54:27 Charles-PC NetworkManager[2350]:
> > > <info>  [1472378067.7994] device (lo): link connected
> > > Aug 28 11:54:27 Charles-PC NetworkManager[2350]:
> > > <info>  [1472378067.7998] manager: (lo): new Generic device
> > > (/org/freedesktop/NetworkManager/Devices/2)
> > > Aug 28 11:54:27 Charles-PC kernel: [   25.907292] r8169 0000:03:00.0
> > > eth0: link down
> > > Aug 28 11:54:27 Charles-PC kernel: [   25.907351] IPv6:
> > > ADDRCONF(NETDEV_UP): eth0: link is not ready
> > > Aug 28 11:54:27 Charles-PC NetworkManager[2350]:
> > > <info>  [1472378067.8743] urfkill disappeared from the bus
> > > 
> > > 
> 
> > 
> > 
> > 
> 
>                                                                                                                      

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