在运行 Ubuntu 22.10 时，我的有线连接有时会断开几秒钟，我需要帮助来确定此问题的根源。我在 Windows 10 上没有遇到任何问题，因为我是双启动的。我设法使用 捕捉到了那一刻journalctl -f。
lis 13 14:47:30 dalibor-desktop org.mozilla.firefox.desktop[3476]: [2022-11-13T13:47:30Z ERROR mp4parse] Found 2 nul bytes in "\0\0"
lis 13 14:48:42 dalibor-desktop dbus-daemon[1050]: [session uid=1000 pid=1050] Activating service name='org.gnome.DejaDup' requested by ':1.107' (uid=1000 pid=3456 comm="/usr/libexec/deja-dup/deja-dup-monitor" label="unconfined")
lis 13 14:48:42 dalibor-desktop dbus-daemon[1050]: [session uid=1000 pid=1050] Successfully activated service 'org.gnome.DejaDup'
lis 13 14:49:08 dalibor-desktop kernel: r8169 0000:04:00.0 enp4s0: Link is Down
lis 13 14:49:14 dalibor-desktop NetworkManager[764]: <info> [1668347354.8045] device (enp4s0): state change: activated -> unavailable (reason 'carrier-changed', sys-iface-state: 'managed')
lis 13 14:49:14 dalibor-desktop NetworkManager[764]: <info> [1668347354.8324] dhcp4 (enp4s0): canceled DHCP transaction
lis 13 14:49:14 dalibor-desktop NetworkManager[764]: <info> [1668347354.8324] dhcp4 (enp4s0): activation: beginning transaction (timeout in 45 seconds)
lis 13 14:49:14 dalibor-desktop NetworkManager[764]: <info> [1668347354.8324] dhcp4 (enp4s0): state changed no lease
lis 13 14:49:14 dalibor-desktop NetworkManager[764]: <info> [1668347354.8326] dhcp6 (enp4s0): canceled DHCP transaction
lis 13 14:49:14 dalibor-desktop NetworkManager[764]: <info> [1668347354.8326] dhcp6 (enp4s0): activation: beginning transaction (timeout in 45 seconds)
lis 13 14:49:14 dalibor-desktop NetworkManager[764]: <info> [1668347354.8326] dhcp6 (enp4s0): state changed no lease
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Withdrawing address record for 10.0.1.19 on enp4s0.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Leaving mDNS multicast group on interface enp4s0.IPv4 with address 10.0.1.19.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Interface enp4s0.IPv4 no longer relevant for mDNS.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Withdrawing address record for 2a00:1028:8d19:f44a:a45f:6900:c16a:e603 on enp4s0.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Withdrawing address record for 2a00:1028:8d19:f44a:e892:88c3:9773:d1bd on enp4s0.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Leaving mDNS multicast group on interface enp4s0.IPv6 with address 2a00:1028:8d19:f44a:e892:88c3:9773:d1bd.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Joining mDNS multicast group on interface enp4s0.IPv6 with address fe80::403d:2d26:b518:ff3b.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Registering new address record for fe80::403d:2d26:b518:ff3b on enp4s0.*.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Withdrawing address record for fe80::403d:2d26:b518:ff3b on enp4s0.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Leaving mDNS multicast group on interface enp4s0.IPv6 with address fe80::403d:2d26:b518:ff3b.
lis 13 14:49:14 dalibor-desktop avahi-daemon[692]: Interface enp4s0.IPv6 no longer relevant for mDNS.
lis 13 14:49:14 dalibor-desktop systemd-resolved[665]: enp4s0: Bus client reset search domain list.
lis 13 14:49:14 dalibor-desktop systemd-resolved[665]: enp4s0: Bus client set default route setting: no
lis 13 14:49:14 dalibor-desktop systemd-resolved[665]: enp4s0: Bus client reset DNS server list.
lis 13 14:49:14 dalibor-desktop NetworkManager[764]: <info> [1668347354.9249] manager: NetworkManager state is now DISCONNECTED
lis 13 14:49:14 dalibor-desktop dbus-daemon[696]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service' requested by ':1.14' (uid=0 pid=764 comm="/usr/sbin/NetworkManager --no-daemon" label="unconfined")
lis 13 14:49:14 dalibor-desktop systemd[1]: Starting Network Manager Script Dispatcher Service...
lis 13 14:49:14 dalibor-desktop dbus-daemon[696]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
lis 13 14:49:14 dalibor-desktop systemd[1]: Started Network Manager Script Dispatcher Service.
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4946] device (enp4s0): carrier: link connected
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4948] device (enp4s0): state change: unavailable -> disconnected (reason 'carrier-changed', sys-iface-state: 'managed')
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4957] policy: auto-activating connection 'Wired connection 1' (830e75e1-7515-3440-9e7c-8347206f808a)
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4961] device (enp4s0): Activation: starting connection 'Wired connection 1' (830e75e1-7515-3440-9e7c-8347206f808a)
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4962] device (enp4s0): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
lis 13 14:49:24 dalibor-desktop kernel: Generic FE-GE Realtek PHY r8169-0-400:00: Downshift occurred from negotiated speed 1Gbps to actual speed 100Mbps, check cabling!
lis 13 14:49:24 dalibor-desktop kernel: r8169 0000:04:00.0 enp4s0: Link is Up - 100Mbps/Full (downshifted) - flow control off
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4965] manager: NetworkManager state is now CONNECTING
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4966] device (enp4s0): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4969] device (enp4s0): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
lis 13 14:49:24 dalibor-desktop NetworkManager[764]: <info> [1668347364.4974] dhcp4 (enp4s0): activation: beginning transaction (timeout in 45 seconds)
lis 13 14:49:24 dalibor-desktop avahi-daemon[692]: Joining mDNS multicast group on interface enp4s0.IPv6 with address fe80::403d:2d26:b518:ff3b.
lis 13 14:49:24 dalibor-desktop avahi-daemon[692]: New relevant interface enp4s0.IPv6 for mDNS.
lis 13 14:49:24 dalibor-desktop avahi-daemon[692]: Registering new address record for fe80::403d:2d26:b518:ff3b on enp4s0.*.
lis 13 14:49:24 dalibor-desktop systemd[1]: NetworkManager-dispatcher.service: Deactivated successfully.
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.2756] dhcp6 (enp4s0): activation: beginning transaction (timeout in 45 seconds)
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.2758] policy: set 'Wired connection 1' (enp4s0) as default for IPv6 routing and DNS
lis 13 14:49:26 dalibor-desktop avahi-daemon[692]: Leaving mDNS multicast group on interface enp4s0.IPv6 with address fe80::403d:2d26:b518:ff3b.
lis 13 14:49:26 dalibor-desktop avahi-daemon[692]: Joining mDNS multicast group on interface enp4s0.IPv6 with address 2a00:1028:8d19:f44a:e892:88c3:9773:d1bd.
lis 13 14:49:26 dalibor-desktop avahi-daemon[692]: Registering new address record for 2a00:1028:8d19:f44a:e892:88c3:9773:d1bd on enp4s0.*.
lis 13 14:49:26 dalibor-desktop avahi-daemon[692]: Withdrawing address record for fe80::403d:2d26:b518:ff3b on enp4s0.
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.2770] dhcp6 (enp4s0): state changed new lease
lis 13 14:49:26 dalibor-desktop dbus-daemon[696]: [system] Activating via systemd: service name='org.freedesktop.nm_dispatcher' unit='dbus-org.freedesktop.nm-dispatcher.service' requested by ':1.14' (uid=0 pid=764 comm="/usr/sbin/NetworkManager --no-daemon" label="unconfined")
lis 13 14:49:26 dalibor-desktop systemd-resolved[665]: enp4s0: Bus client set search domain list to: home
lis 13 14:49:26 dalibor-desktop systemd-resolved[665]: enp4s0: Bus client set default route setting: yes
lis 13 14:49:26 dalibor-desktop systemd-resolved[665]: enp4s0: Bus client set DNS server list to: 2a00:1028:8d19:f44a:828c:97ff:fedf:b40e
lis 13 14:49:26 dalibor-desktop systemd[1]: Starting Network Manager Script Dispatcher Service...
lis 13 14:49:26 dalibor-desktop dbus-daemon[696]: [system] Successfully activated service 'org.freedesktop.nm_dispatcher'
lis 13 14:49:26 dalibor-desktop systemd[1]: Started Network Manager Script Dispatcher Service.
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.5116] dhcp4 (enp4s0): state changed new lease, address=10.0.1.19
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.5119] policy: set 'Wired connection 1' (enp4s0) as default for IPv4 routing and DNS
lis 13 14:49:26 dalibor-desktop avahi-daemon[692]: Joining mDNS multicast group on interface enp4s0.IPv4 with address 10.0.1.19.
lis 13 14:49:26 dalibor-desktop avahi-daemon[692]: New relevant interface enp4s0.IPv4 for mDNS.
lis 13 14:49:26 dalibor-desktop avahi-daemon[692]: Registering new address record for 10.0.1.19 on enp4s0.IPv4.
lis 13 14:49:26 dalibor-desktop systemd-resolved[665]: enp4s0: Bus client set DNS server list to: 10.0.1.138, 2a00:1028:8d19:f44a:828c:97ff:fedf:b40e
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.5153] device (enp4s0): state change: ip-config -> ip-check (reason 'none', sys-iface-state: 'managed')
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.5171] device (enp4s0): state change: ip-check -> secondaries (reason 'none', sys-iface-state: 'managed')
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.5172] device (enp4s0): state change: secondaries -> activated (reason 'none', sys-iface-state: 'managed')
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.5174] manager: NetworkManager state is now CONNECTED_SITE
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.5176] device (enp4s0): Activation: successful, device activated.
lis 13 14:49:26 dalibor-desktop NetworkManager[764]: <info> [1668347366.7830] manager: NetworkManager state is now CONNECTED_GLOBAL
lis 13 14:49:27 dalibor-desktop avahi-daemon[692]: Registering new address record for 2a00:1028:8d19:f44a:158e:9cd0:1f76:43f4 on enp4s0.*.
lis 13 14:49:36 dalibor-desktop systemd[1]: NetworkManager-dispatcher.service: Deactivated successfully.
lis 13 14:49:39 dalibor-desktop systemd[1]: Starting Download data for packages that failed at package install time...
lis 13 14:49:39 dalibor-desktop systemd[1]: update-notifier-download.service: Deactivated successfully.
lis 13 14:49:39 dalibor-desktop systemd[1]: Finished Download data for packages that failed at package install time.
lis 13 14:49:39 dalibor-desktop dbus-daemon[696]: [system] Activating via systemd: service name='org.freedesktop.timedate1' unit='dbus-org.freedesktop.timedate1.service' requested by ':1.20' (uid=0 pid=719 comm="/usr/lib/snapd/snapd" label="unconfined")
lis 13 14:49:39 dalibor-desktop systemd[1]: Starting Time & Date Service...
lis 13 14:49:39 dalibor-desktop dbus-daemon[696]: [system] Successfully activated service 'org.freedesktop.timedate1'
lis 13 14:49:39 dalibor-desktop systemd[1]: Started Time & Date Service.
lis 13 14:49:45 dalibor-desktop dbus-daemon[1050]: [session uid=1000 pid=1050] Activating service name='org.gnome.TextEditor' requested by ':1.46' (uid=1000 pid=1554 comm="/usr/bin/gnome-shell" label="unconfined")
lis 13 14:49:45 dalibor-desktop dbus-daemon[1050]: [session uid=1000 pid=1050] Successfully activated service 'org.gnome.TextEditor'
lis 13 14:49:46 dalibor-desktop gnome-shell[1554]: Window manager warning: Buggy client sent a _NET_ACTIVE_WINDOW message with a timestamp of 0 for 0x2a00005
其中有一行特别写道：
lis 13 14:49:24 dalibor-desktop kernel: Generic FE-GE Realtek PHY r8169-0-400:00: Downshift occurred from negotiated speed 1Gbps to actual speed 100Mbps, check cabling!
我使用的电缆已经很旧了，但由于我在 Windows 上没有遇到任何问题，所以我认为问题出在其他地方。
请帮我找出问题所在。如有必要，我将提供更多日志。
编辑：sudo dmesg | grep -e enp -e Network输出：
[ 5.754095] r8168 0000:04:00.0 enp4s0: renamed from eth0
[ 8.291679] enp4s0: 0xffffb4c100121000, d8:5e:d3:ad:b0:0e, IRQ 36
[ 22.698420] r8168: enp4s0: link up
[ 22.698490] IPv6: ADDRCONF(NETDEV_CHANGE): enp4s0: link becomes ready
[ 1715.242846] r8168: enp4s0: link down
[ 1729.626331] r8168: enp4s0: link up
[ 1763.400367] r8168: enp4s0: link down
[ 1777.787672] r8168: enp4s0: link up
[ 2138.192663] r8168: enp4s0: link down
[ 2152.571593] r8168: enp4s0: link up