Networkmanager disconnects every few minutes

After recent zypper dup networkmanager start disconnect ethernet (internet) connection every few minutes. What is the problem could be and how to solve?

Please monitor the NetworkManager logging in a terminal with

sudo journalctl -fu NetworkManager

and capture the relevant output when disconnection occurs. Post here for others to advise further.

If preferred you can redirect the output to a text file, and review later…

sudo journalctl -fu NetworkManager > output.txt

Will do. It actually does not disconnect: it stops to receive incoming packages. Disconnect/Connect interface in NM-applet helps to restart and resume connection and incoming packages.

Ok, that’s a slightly different description to that mentioned in your opening post. Is this all traffic? You could try a constant ping to a well known internet address? Are you using a VPN? More info required here.

You could also check that the interface is negotiating correctly perhaps…

/usr/sbin/ethtool eth0

Unplug and re-plug a few times to ensure that it is consistent.

Yes, all traffic. Not using VPN. Not reproducible today after PC start. Yesterday set MTU to 8192, added


lines to /etc/NetworkManager/NetworkManager.conf

> /usr/sbin/ethtool enp6s7
Settings for enp6s7:
        Supported ports:  TP MII ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Supported pause frame use: No
        Supports auto-negotiation: Yes
        Supported FEC modes: Not reported
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
        Advertised pause frame use: No
        Advertised auto-negotiation: Yes
        Advertised FEC modes: Not reported
        Link partner advertised link modes:  10baseT/Half 10baseT/Full
                                             100baseT/Half 100baseT/Full
        Link partner advertised pause frame use: Symmetric
        Link partner advertised auto-negotiation: Yes
        Link partner advertised FEC modes: Not reported
        Speed: 100Mb/s
        Duplex: Full
        Port: MII
        PHYAD: 32
        Transceiver: internal
        Auto-negotiation: on
Cannot get wake-on-lan settings: Operation not permitted
        Current message level: 0x00000007 (7)
                               drv probe link
        Link detected: yes