Losing network connection

My freshly installed ZorinOS 15.3 Core is facing troubles with its network connection to a pfSense firewall on FreeBSD OS and hardware from PC Engines APU2 to provide a VPN, which is in another network and gets its 172-address. Zorin gets its IPv4 by DHCP of the VPN gateway and initally has access to the internet. After a while, like randomly after a while of minutes to hours, a question mark appears on the network adapter symbol on the task list and it turns dark grey and has no internet connection. I can’t ping the default gateway either, also I can’t ping the ZorinOS client from the gateway. Windows 10 works great with the pfSense APU2 and as opposed to ZorinOS keeps its IP address after reboot, as the DHCP lease lease time and maxmum lease time suggest. I have the same issue with a static IP.

The ethernet controller is an Intel Corporation 82579LM Gigabit Network Connection (Lewisville) (rev 04), driver version is 3.2.6-k.

After I set the ethernet adapter down with ip link set eno1 down, wait and set it up again, I again have connection to the internet for a while with the same IP. This might be an indication for the cause?

I connect cable, get IP inet 10.11.0.128/16 scope global dynamic
valid_lft 431955sec preferred_lft 431955sec and have network/internet. Then the network icon turns dark grey with a question mark and I have neither access to the internet nor the gateway and journal-ctl -u NetworkManager shows (only) “NetworkManager state is now CONNECTED_SITE”.

The network interface on the APU2 seems not to be down.

What can I do to solve the problem and find out more by e. g. raise the verbosity level of NetworkManager? Or do you have an idea what the cause could be?

Could you please enter your network settings and turn off ipv6, then test?

I turned it off on the gateway, should I do so on the ZorinOS client?

nmcli con show "Wired connection 1" shows*:

connection.id:                          Wired connection 1
connection.uuid:                        2bbf67dd-db7b-3970-bebc-9dcc0bee92d2
connection.stable-id:                   --
connection.type:                        802-3-ethernet
connection.interface-name:              --
connection.autoconnect:                 yes
connection.autoconnect-priority:        -999
connection.autoconnect-retries:         -1 (default)
connection.auth-retries:                -1
connection.timestamp:                   1613566624
connection.read-only:                   no
connection.permissions:                 --
connection.zone:                        --
connection.master:                      --
connection.slave-type:                  --
connection.autoconnect-slaves:          -1 (default)
connection.secondaries:                 --
connection.gateway-ping-timeout:        0
connection.metered:                     unknown
connection.lldp:                        default
connection.mdns:                        -1 (default)
802-3-ethernet.port:                    --
802-3-ethernet.speed:                   0
802-3-ethernet.duplex:                  --
802-3-ethernet.auto-negotiate:          no
802-3-ethernet.mac-address:             2C:27:D7:3B:D1:2B
802-3-ethernet.cloned-mac-address:      --
802-3-ethernet.generate-mac-address-mask:--
802-3-ethernet.mac-address-blacklist:   --
802-3-ethernet.mtu:                     auto
802-3-ethernet.s390-subchannels:        --
802-3-ethernet.s390-nettype:            --
802-3-ethernet.s390-options:            --
802-3-ethernet.wake-on-lan:             default
802-3-ethernet.wake-on-lan-password:    --
ipv4.method:                            auto
ipv4.dns:                               --
ipv4.dns-search:                        *************
ipv4.dns-options:                       ""
ipv4.dns-priority:                      0
ipv4.addresses:                         --
ipv4.gateway:                           --
ipv4.routes:                            --
ipv4.route-metric:                      -1
ipv4.route-table:                       0 (unspec)
ipv4.ignore-auto-routes:                no
ipv4.ignore-auto-dns:                   no
ipv4.dhcp-client-id:                    --
ipv4.dhcp-timeout:                      0 (default)
ipv4.dhcp-send-hostname:                yes
ipv4.dhcp-hostname:                     --
ipv4.dhcp-fqdn:                         --
ipv4.never-default:                     no
ipv4.may-fail:                          yes
ipv4.dad-timeout:                       -1 (default)
ipv6.method:                            auto
ipv6.dns:                               --
ipv6.dns-search:                        --
ipv6.dns-options:                       ""
ipv6.dns-priority:                      0
ipv6.addresses:                         --
ipv6.gateway:                           --
ipv6.routes:                            --
ipv6.route-metric:                      -1
ipv6.route-table:                       0 (unspec)
ipv6.ignore-auto-routes:                no
ipv6.ignore-auto-dns:                   no
ipv6.never-default:                     no
ipv6.may-fail:                          yes
ipv6.ip6-privacy:                       -1 (unknown)
ipv6.addr-gen-mode:                     stable-privacy
ipv6.dhcp-send-hostname:                yes
ipv6.dhcp-hostname:                     --
ipv6.token:                             --
proxy.method:                           none
proxy.browser-only:                     no
proxy.pac-url:                          --
proxy.pac-script:                       --
GENERAL.NAME:                           Wired connection 1
GENERAL.UUID:                           2bbf67dd-db7b-3970-bebc-9dcc0bee92d2
GENERAL.DEVICES:                        eno1
GENERAL.STATE:                          activated
GENERAL.DEFAULT:                        yes
GENERAL.DEFAULT6:                       no
GENERAL.SPEC-OBJECT:                    --
GENERAL.VPN:                            no
GENERAL.DBUS-PATH:                      /org/freedesktop/NetworkManager/ActiveConnection/5
GENERAL.CON-PATH:                       /org/freedesktop/NetworkManager/Settings/1
GENERAL.ZONE:                           --
GENERAL.MASTER-PATH:                    --
IP4.ADDRESS[1]:                         10.11.0.129/16
IP4.GATEWAY:                            10.11.0.1
IP4.ROUTE[1]:                           dst = 0.0.0.0/0, nh = 10.11.0.1, mt = 100
IP4.ROUTE[2]:                           dst = 10.11.0.0/16, nh = 0.0.0.0, mt = 100
IP4.ROUTE[3]:                           dst = 169.254.0.0/16, nh = 0.0.0.0, mt = 1000
IP4.DNS[1]:                             10.10.0.1
IP4.DOMAIN[1]:                          ************
DHCP4.OPTION[1]:                        domain_name_servers = 10.10.0.1
DHCP4.OPTION[2]:                        requested_domain_search = 1
DHCP4.OPTION[3]:                        network_number = 10.11.0.0
DHCP4.OPTION[4]:                        requested_time_offset = 1
DHCP4.OPTION[5]:                        requested_broadcast_address = 1
DHCP4.OPTION[6]:                        requested_rfc3442_classless_static_routes = 1
DHCP4.OPTION[7]:                        requested_domain_name = 1
DHCP4.OPTION[8]:                        requested_netbios_scope = 1
DHCP4.OPTION[9]:                        requested_wpad = 1
DHCP4.OPTION[10]:                       next_server = 0.0.0.0
DHCP4.OPTION[11]:                       domain_name = ************
DHCP4.OPTION[12]:                       requested_interface_mtu = 1
DHCP4.OPTION[13]:                       requested_subnet_mask = 1
DHCP4.OPTION[14]:                       expiry = 1613911002
DHCP4.OPTION[15]:                       ip_address = 10.11.0.129
DHCP4.OPTION[16]:                       dhcp_lease_time = 352212
DHCP4.OPTION[17]:                       requested_domain_name_servers = 1
DHCP4.OPTION[18]:                       subnet_mask = 255.255.0.0
DHCP4.OPTION[19]:                       requested_static_routes = 1
DHCP4.OPTION[20]:                       broadcast_address = 10.11.255.255
DHCP4.OPTION[21]:                       requested_ntp_servers = 1
DHCP4.OPTION[22]:                       requested_netbios_name_servers = 1
DHCP4.OPTION[23]:                       routers = 10.11.0.1
DHCP4.OPTION[24]:                       requested_ms_classless_static_routes = 1
DHCP4.OPTION[25]:                       requested_routers = 1
DHCP4.OPTION[26]:                       dhcp_message_type = 5
DHCP4.OPTION[27]:                       requested_host_name = 1
DHCP4.OPTION[28]:                       dhcp_server_identifier = 10.11.0.1
IP6.ADDRESS[1]:                         fe80::4470:77f1:df79:d3a/64
IP6.GATEWAY:                            --
IP6.ROUTE[1]:                           dst = ff00::/8, nh = ::, mt = 256, table=255
IP6.ROUTE[2]:                           dst = fe80::/64, nh = ::, mt = 256
IP6.ROUTE[3]:                           dst = fe80::/64, nh = ::, mt = 100

* be aware that I ************* out the domain name which is the same value everywhere.

Today I had no trouble at all. Only thing I was doing is running tcptrack.

I disabled IPv6 but the issue is still there. nmcli con show ... shows:
ipv6.method: ignore

I left everything over night, the next morning (as the day before when I left) I had connection. But after a reboot I lost the connection. Here is the log with the reboot indicated (-- Reboot --):

Feb 24 15:05:13 ************.*****.** dhclient[1264]: receive_packet failed on eno1: Network is down
Feb 24 15:05:19 ************.*****.** NetworkManager[727]: <info>  [1614175519.8028] device (eno1): state change: activated -> unavailable (reason 'carrier-changed', sys-iface-state: 'managed')
Feb 24 15:05:19 ************.*****.** NetworkManager[727]: <info>  [1614175519.8188] dhcp4 (eno1): canceled DHCP transaction, DHCP client pid 1264
Feb 24 15:05:19 ************.*****.** NetworkManager[727]: <info>  [1614175519.8189] dhcp4 (eno1): state changed bound -> done
Feb 24 15:05:19 ************.*****.** NetworkManager[727]: <info>  [1614175519.8203] manager: NetworkManager state is now CONNECTED_LOCAL
Feb 24 15:05:19 ************.*****.** NetworkManager[727]: <info>  [1614175519.8206] manager: NetworkManager state is now DISCONNECTED
Feb 24 15:05:29 ************.*****.** NetworkManager[727]: <info>  [1614175529.9968] device (eno1): carrier: link connected
Feb 24 15:05:29 ************.*****.** NetworkManager[727]: <info>  [1614175529.9972] device (eno1): state change: unavailable -> disconnected (reason 'carrier-changed', sys-iface-state: 'managed')
Feb 24 15:05:29 ************.*****.** NetworkManager[727]: <info>  [1614175529.9982] policy: auto-activating connection 'Wired connection 1'
Feb 24 15:05:29 ************.*****.** NetworkManager[727]: <info>  [1614175529.9999] device (eno1): Activation: starting connection 'Wired connection 1' (2bbf67dd-db7b-3970-bebc-9dcc0bee92d2)
Feb 24 15:05:30 ************.*****.** NetworkManager[727]: <info>  [1614175530.0006] device (eno1): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
Feb 24 15:05:30 ************.*****.** NetworkManager[727]: <info>  [1614175530.0011] manager: NetworkManager state is now CONNECTING
Feb 24 15:05:30 ************.*****.** NetworkManager[727]: <info>  [1614175530.0017] device (eno1): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
Feb 24 15:05:30 ************.*****.** NetworkManager[727]: <info>  [1614175530.0023] device (eno1): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
Feb 24 15:05:30 ************.*****.** NetworkManager[727]: <info>  [1614175530.0029] dhcp4 (eno1): activation: beginning transaction (timeout in 45 seconds)
Feb 24 15:05:30 ************.*****.** NetworkManager[727]: <info>  [1614175530.0066] dhcp4 (eno1): dhclient started with pid 2999
Feb 24 15:05:30 ************.*****.** dhclient[2999]: DHCPREQUEST of 10.11.0.135 on eno1 to 255.255.255.255 port 67 (xid=0x14547754)
Feb 24 15:05:30 ************.*****.** dhclient[2999]: DHCPNAK from 10.11.0.1 (xid=0x54775414)
Feb 24 15:05:30 ************.*****.** NetworkManager[727]: <info>  [1614175530.0424] dhcp4 (eno1): state changed unknown -> expire
Feb 24 15:05:30 ************.*****.** NetworkManager[727]: <info>  [1614175530.0457] dhcp4 (eno1): state changed expire -> unknown
Feb 24 15:05:30 ************.*****.** dhclient[2999]: DHCPDISCOVER on eno1 to 255.255.255.255 port 67 interval 3 (xid=0xa3475f77)
Feb 24 15:05:31 ************.*****.** dhclient[2999]: DHCPREQUEST of 10.11.0.136 on eno1 to 255.255.255.255 port 67 (xid=0x775f47a3)
Feb 24 15:05:31 ************.*****.** dhclient[2999]: DHCPOFFER of 10.11.0.136 from 10.11.0.1
Feb 24 15:05:31 ************.*****.** dhclient[2999]: DHCPACK of 10.11.0.136 from 10.11.0.1
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1850] dhcp4 (eno1):   address 10.11.0.136
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1851] dhcp4 (eno1):   plen 16 (255.255.0.0)
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1851] dhcp4 (eno1):   gateway 10.11.0.1
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1851] dhcp4 (eno1):   lease time 432000
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1852] dhcp4 (eno1):   nameserver '10.10.0.1'
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1852] dhcp4 (eno1):   domain name '*****.**'
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1852] dhcp4 (eno1): state changed unknown -> bound
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1890] device (eno1): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'managed')
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1902] device (eno1): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'managed')
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1905] device (eno1): state change: secondaries -> activated (reason 'none', sys-iface-state: 'managed')
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.1907] manager: NetworkManager state is now CONNECTED_LOCAL
Feb 24 15:05:31 ************.*****.** dhclient[2999]: bound to 10.11.0.136 -- renewal in 182103 seconds.
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.2039] manager: NetworkManager state is now CONNECTED_SITE
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.2041] policy: set 'Wired connection 1' (eno1) as default for IPv4 routing and DNS
Feb 24 15:05:31 ************.*****.** NetworkManager[727]: <info>  [1614175531.2044] device (eno1): Activation: successful, device activated.
Feb 24 15:05:32 ************.*****.** NetworkManager[727]: <info>  [1614175532.5025] manager: NetworkManager state is now CONNECTED_GLOBAL
Feb 25 09:43:39 ************.*****.** NetworkManager[727]: <info>  [1614242619.7174] modem-manager: ModemManager no longer available
Feb 25 09:43:40 ************.*****.** NetworkManager[727]: <warn>  [1614242620.4743] error requesting auth for org.freedesktop.NetworkManager.wifi.share.protected: Authorization check failed: Refusing activation, D-Bus is shutting down.
Feb 25 09:43:40 ************.*****.** NetworkManager[727]: <warn>  [1614242620.4743] error requesting auth for org.freedesktop.NetworkManager.wifi.share.open: Authorization check failed: Refusing activation, D-Bus is shutting down.
Feb 25 09:43:40 ************.*****.** NetworkManager[727]: <info>  [1614242620.8516] caught SIGTERM, shutting down normally.
Feb 25 09:43:40 ************.*****.** systemd[1]: Stopping Network Manager...
Feb 25 09:43:40 ************.*****.** NetworkManager[727]: <info>  [1614242620.8649] exiting (success)
Feb 25 09:43:40 ************.*****.** systemd[1]: Stopped Network Manager.
-- Reboot --
Feb 25 09:44:01 ************.*****.** systemd[1]: Starting Network Manager...
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4058] NetworkManager (version 1.10.6) is starting... (for the first time)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4058] Read config: /etc/NetworkManager/NetworkManager.conf (lib: 10-dns-resolved.conf, 20-connectivity-zorin.conf, no-mac-addr-change.conf) (etc: 10-globally-managed-devices.conf, default-wifi-powersave-on.conf)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4129] manager[0x55839c842050]: monitoring kernel firmware directory '/lib/firmware'.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4129] monitoring ifupdown state file '/run/network/ifstate'.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4316] hostname: hostname: using hostnamed
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4317] hostname: hostname changed from (none) to "************.*****.**"
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4319] dns-mgr[0x55839c833190]: init: dns=systemd-resolved, rc-manager=symlink, plugin=systemd-resolved
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4323] manager[0x55839c842050]: rfkill: WiFi hardware radio set enabled
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4324] manager[0x55839c842050]: rfkill: WWAN hardware radio set enabled
Feb 25 09:44:01 ************.*****.** systemd[1]: Started Network Manager.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4629] init!
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4630]       interface-parser: parsing file /etc/network/interfaces
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4630]       interface-parser: finished parsing file /etc/network/interfaces
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4630] management mode: unmanaged
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4633] devices added (path: /sys/devices/pci0000:00/0000:00:19.0/net/eno1, iface: eno1)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4633] device added (path: /sys/devices/pci0000:00/0000:00:19.0/net/eno1, iface: eno1): no ifupdown configuration found.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4633] devices added (path: /sys/devices/virtual/net/lo, iface: lo)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4634] device added (path: /sys/devices/virtual/net/lo, iface: lo): no ifupdown configuration found.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4634] end _init.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4634] 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)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4634] settings: loaded plugin keyfile: (c) 2007 - 2016 Red Hat, Inc.  To report bugs please use the NetworkManager mailing list.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4634] (-1668819712) ... get_connections.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4634] (-1668819712) ... get_connections (managed=false): return empty list.
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4797] keyfile: new connection /etc/NetworkManager/system-connections/Wired connection 1 (2bbf67dd-db7b-3970-bebc-9dcc0bee92d2,"Wired connection 1")
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4800] get unmanaged devices count: 0
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4801] manager: rfkill: WiFi enabled by radio killswitch; enabled by state file
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4802] manager: rfkill: WWAN enabled by radio killswitch; enabled by state file
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4802] manager: Networking is enabled by state file
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4803] dhcp-init: Using DHCP client 'dhclient'
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4804] Loaded device plugin: NMBondDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4804] Loaded device plugin: NMBridgeDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4804] Loaded device plugin: NMDummyDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4804] Loaded device plugin: NMEthernetDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4804] Loaded device plugin: NMInfinibandDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4804] Loaded device plugin: NMIPTunnelDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4805] Loaded device plugin: NMMacsecDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4805] Loaded device plugin: NMMacvlanDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4805] Loaded device plugin: NMPppDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4805] Loaded device plugin: NMTunDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4805] Loaded device plugin: NMVethDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4805] Loaded device plugin: NMVlanDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4805] Loaded device plugin: NMVxlanDeviceFactory (internal)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4808] Loaded device plugin: NMWifiFactory (/usr/lib/x86_64-linux-gnu/NetworkManager/libnm-device-plugin-wifi.so)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4810] Loaded device plugin: NMAtmManager (/usr/lib/x86_64-linux-gnu/NetworkManager/libnm-device-plugin-adsl.so)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4815] Loaded device plugin: NMWwanFactory (/usr/lib/x86_64-linux-gnu/NetworkManager/libnm-device-plugin-wwan.so)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4838] Loaded device plugin: NMBluezManager (/usr/lib/x86_64-linux-gnu/NetworkManager/libnm-device-plugin-bluetooth.so)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4851] Loaded device plugin: NMTeamFactory (/usr/lib/x86_64-linux-gnu/NetworkManager/libnm-device-plugin-team.so)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4861] device (lo): carrier: link connected
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4866] manager: (lo): new Generic device (/org/freedesktop/NetworkManager/Devices/1)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4881] manager: (eno1): new Ethernet device (/org/freedesktop/NetworkManager/Devices/2)
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.4894] device (eno1): state change: unmanaged -> unavailable (reason 'managed', sys-iface-state: 'external')
Feb 25 09:44:01 ************.*****.** NetworkManager[753]: <info>  [1614242641.7216] modem-manager: ModemManager available
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8542] device (eno1): carrier: link connected
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8547] device (eno1): state change: unavailable -> disconnected (reason 'carrier-changed', sys-iface-state: 'managed')
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8552] policy: auto-activating connection 'Wired connection 1'
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8561] device (eno1): Activation: starting connection 'Wired connection 1' (2bbf67dd-db7b-3970-bebc-9dcc0bee92d2)
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8562] device (eno1): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8563] manager: NetworkManager state is now CONNECTING
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8565] device (eno1): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8569] device (eno1): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8613] dhcp4 (eno1): activation: beginning transaction (timeout in 45 seconds)
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.8753] dhcp4 (eno1): dhclient started with pid 1053
Feb 25 09:44:04 ************.*****.** dhclient[1053]: DHCPREQUEST of 10.11.0.136 on eno1 to 255.255.255.255 port 67 (xid=0x607974d)
Feb 25 09:44:04 ************.*****.** dhclient[1053]: DHCPNAK from 10.11.0.1 (xid=0x4d970706)
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.9114] dhcp4 (eno1): state changed unknown -> expire
Feb 25 09:44:04 ************.*****.** NetworkManager[753]: <info>  [1614242644.9144] dhcp4 (eno1): state changed expire -> unknown
Feb 25 09:44:04 ************.*****.** dhclient[1053]: DHCPDISCOVER on eno1 to 255.255.255.255 port 67 interval 3 (xid=0x60ac1e32)
Feb 25 09:44:05 ************.*****.** dhclient[1053]: DHCPREQUEST of 10.11.0.137 on eno1 to 255.255.255.255 port 67 (xid=0x321eac60)
Feb 25 09:44:05 ************.*****.** dhclient[1053]: DHCPOFFER of 10.11.0.137 from 10.11.0.1
Feb 25 09:44:06 ************.*****.** dhclient[1053]: DHCPACK of 10.11.0.137 from 10.11.0.1
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0147] dhcp4 (eno1):   address 10.11.0.137
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0147] dhcp4 (eno1):   plen 16 (255.255.0.0)
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0147] dhcp4 (eno1):   gateway 10.11.0.1
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0147] dhcp4 (eno1):   lease time 432000
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0147] dhcp4 (eno1):   nameserver '10.10.0.1'
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0147] dhcp4 (eno1):   domain name '*****.**'
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0148] dhcp4 (eno1): state changed unknown -> bound
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0160] device (eno1): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'managed')
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0165] device (eno1): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'managed')
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0167] device (eno1): state change: secondaries -> activated (reason 'none', sys-iface-state: 'managed')
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0168] manager: NetworkManager state is now CONNECTED_LOCAL
Feb 25 09:44:06 ************.*****.** dhclient[1053]: bound to 10.11.0.137 -- renewal in 188164 seconds.
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0317] manager: NetworkManager state is now CONNECTED_SITE
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0318] policy: set 'Wired connection 1' (eno1) as default for IPv4 routing and DNS
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0320] device (eno1): Activation: successful, device activated.
Feb 25 09:44:06 ************.*****.** NetworkManager[753]: <info>  [1614242646.0324] manager: startup complete
Feb 25 09:44:07 ************.*****.** NetworkManager[753]: <info>  [1614242647.3381] manager: NetworkManager state is now CONNECTED_GLOBAL
Feb 25 09:49:21 ************.*****.** NetworkManager[753]: <info>  [1614242961.6399] manager: NetworkManager state is now CONNECTED_SITE

I see some settings to enabled; can you relay the output of

rfkill list all

rfkill list all with sudo privileges doesn’t have any output.

root@localhost:~# rfkill list all
root@localhost:~#

Can you post the output of

/etc/NetworkManager/NetworkManager.conf

And

lspci | egrep -i --color ‘network|ethernet|wireless|wi-fi’

Thanks for your help. I hope the time I take to reply is o. k. for you.

The connection is stable if there is a layer 2 switch in between, but however if I start up the computer I still need to ip link set eno1 down and up sometimes to have internet and connection to the gateway.

Output is as follows:

me@localhost:~$ cat /etc/NetworkManager/NetworkManager.conf
[main]
plugins=ifupdown,keyfile

[ifupdown]
managed=false

[device]
wifi.scan-rand-mac-address=no

and

me@localhost:~$ lspci | egrep -i --color 'network|ethernet|wireless|wi-fi'
00:19.0 Ethernet controller: Intel Corporation 82579LM Gigabit Network Connection (Lewisville) (rev 04)

Everything there looks perfect.

Here is a thread with several good suggestions to try, including powersave and WICD which are known to often help wifi drop:

It may be better for you to go over the whole thread and compare against your memory what you have tried, so far.