'no' internet connection within appcenter

Question

Ive setup my little debianserver as a dhcp/dns server using dnsmasq. Everything is working perfectly fine, i do get an internal address assigned. I have a connection to the internet. The dns servers from my isp also work. However despite it working elementaryOS tells me in the top right corner that i do not have an internet connection and in the network settings everything is Unknown. Yet when i type ifconfig in the terminal everything is configured properly. This would not be a big deal since everything is mostly working, BUT the AppCenter is not. I cannot download anything in the AppCenter anymore as it also complains about no internet connection. The funny thing is the Network settings in elementaryos even seem to track how much i uploaded and downloaded in my current session, with my supposedly non-existent internet connection.

Thats the output of ifconfig in case this helps.

eno1      Link encap:Ethernet  HWaddr 78:24:af:8a:e4:04  
          inet addr:192.168.1.100  Bcast:192.168.1.255  Mask:255.255.255.0
          inet6 addr: fe80::7a24:afff:fe8a:e404/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:18504 errors:0 dropped:0 overruns:0 frame:0
          TX packets:13314 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:20115123 (20.1 MB)  TX bytes:1612634 (1.6 MB)
          Interrupt:20 Memory:df100000-df120000 

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:65536  Metric:1
          RX packets:198 errors:0 dropped:0 overruns:0 frame:0
          TX packets:198 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1 
          RX bytes:14610 (14.6 KB)  TX bytes:14610 (14.6 KB)

Answer 1

I figured out what was causing the issue.

By default, if you even dare you mention a device inside /etc/network/interfaces at all, even if its just

auto eno1
 iface eno1 inet dhcp

something like this, witch is what i had put in there, NetworkManager will ignore the device (in my case eno1 aka my LAN) completely.

All i had to do is delete this from the file and then restart the network-manager service.

And appearently appcenter is one of the few applications that does not actually check if you have an internet connection, but instead just asks NetworkManager if it has an internet connection.