I am also seeing this same problem on a Raspberry Pi4 4GB. I purchased the Pi last November and installed from the then-available 2019-09-26-raspbian-buster.zip but routinely keep it updated (apt update / apt upgrade).
The Pi was rock solid and did not exhibit any problems until 2020-02-24 when I applied some updates followed by a "sudo reboot" but the boot process did not complete. The Pi runs headless so I don't know whether it never actually completed the shutdown, or failed to reboot. I power- cycled the device and it came back OK. Another set of updates were applied on 2020-03-11 and the subsequent reboot completed without incident so I assumed the earlier problem was a one-off. Then, on 2020-03-14 the Pi froze. Wouldn't respond to pings, ssh or vnc. It is Ethernet-connected but the WiFi interface is active and it did not occur to me to try connecting via WiFi. I just did another power-cycle and then started nosing around through the logs. Which brought me to: Mar 14 12:48:16 iot-hub avahi-daemon[361]: Withdrawing address record for 192.168.132.60 on eth0. Mar 14 12:48:16 iot-hub avahi-daemon[361]: Leaving mDNS multicast group on interface eth0.IPv4 with address 192.168.132.60. Mar 14 12:48:16 iot-hub avahi-daemon[361]: Interface eth0.IPv4 no longer relevant for mDNS. and, from there, to this post. The main reasons I'm adding a comment to this post are (a) as a "me too" as of March 2020, and (b) in case the pattern of the RPi being perfectly OK until 2020-02-24 causes someone to say "ahah!" The updates in question were (from the history log): Upgrade: libpython3.7-minimal:armhf (3.7.3-2, 3.7.3-2+deb10u1), libraspberrypi- bin:armhf (1.20200114-1, 1.20200212-1), libopenjp2-7:armhf (2.3.0-2, 2.3.0-2+deb10u1), rc-gui:armhf (1.34, 1.36), libcom-err2:armhf (1.44.5-1+deb10u2, 1.44.5-1+deb10u3), libcups2:armhf (2.2.10-6+deb10u1, 2.2.10-6+deb10u2), libraspberrypi-dev:armhf (1.20200114-1, 1.20200212-1), libraspberrypi-doc:armhf (1.20200114-1, 1.20200212-1), python3.7-venv:armhf (3.7.3-2, 3.7.3-2+deb10u1), raspberrypi-ui- mods:armhf (1.20200127, 1.20200218), qt5-gtk-platformtheme:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), libfm4:armhf (1.3.1-1+rpt12, 1.3.1-1+rpt13), libsystemd0:armhf (241-7~deb10u2+rpi1, 241-7~deb10u3+rpi1), raspi-config:armhf (20200205, 20200207), libfm- modules:armhf (1.3.1-1+rpt12, 1.3.1-1+rpt13), libfm-extra4:armhf (1.3.1-1+rpt12, 1.3.1-1+rpt13), mariadb-common:armhf (1:10.3.17-0+deb10u1, 1:10.3.22-0+deb10u1), binutils:armhf (2.31.1-16+rpi1, 2.31.1-16+rpi2), e2fsprogs:armhf (1.44.5-1+deb10u2, 1.44.5-1+deb10u3), sudo:armhf (1.8.27-1+deb10u1, 1.8.27-1+deb10u2), libqt5dbus5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), libqt5sql5-sqlite:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), python3-pil:armhf (5.4.1-2, 5.4.1-2+deb10u1), libpython3.7:armhf (3.7.3-2, 3.7.3-2+deb10u1), python3.7:armhf (3.7.3-2, 3.7.3-2+deb10u1), openssh-sftp-server:armhf (1:7.9p1-10+deb10u1, 1:7.9p1-10+deb10u2), libqt5widgets5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), libfm-gtk4:armhf (1.3.1-1+rpt12, 1.3.1-1+rpt13), udev:armhf (241-7~deb10u2+rpi1, 241-7~deb10u3+rpi1), python3.7-dev:armhf (3.7.3-2, 3.7.3-2+deb10u1), binutils-arm-linux-gnueabihf:armhf (2.31.1-16+rpi1, 2.31.1-16+rpi2), libpython3.7-stdlib:armhf (3.7.3-2, 3.7.3-2+deb10u1), libudev1:armhf (241-7~deb10u2+rpi1, 241-7~deb10u3+rpi1), python3.7-minimal:armhf (3.7.3-2, 3.7.3-2+deb10u1), libqt5xml5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), libqt5printsupport5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), raspberrypi- kernel:armhf (1.20200114-1, 1.20200212-1), libss2:armhf (1.44.5-1+deb10u2, 1.44.5-1+deb10u3), libqt5concurrent5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), libext2fs2:armhf (1.44.5-1+deb10u2, 1.44.5-1+deb10u3), raspberrypi-bootloader:armhf (1.20200114-1, 1.20200212-1), libexif12:armhf (0.6.21-5.1, 0.6.21-5.1+deb10u1), libqt5gui5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), libimobiledevice6:armhf (1.2.1~git20181030.92c5462-1, 1.2.1~git20181030.92c5462-2), gldriver- test:armhf (0.4, 0.5), ssh:armhf (1:7.9p1-10+deb10u1, 1:7.9p1-10+deb10u2), systemd-sysv:armhf (241-7~deb10u2+rpi1, 241-7~deb10u3+rpi1), guile-2.2-libs:armhf (2.2.4+1-2, 2.2.4+1-2+deb10u1), realvnc-vnc-server:armhf (6.6.0.41949, 6.7.1.42348), libpython3.7-dev:armhf (3.7.3-2, 3.7.3-2+deb10u1), libpam-systemd:armhf (241-7~deb10u2+rpi1, 241-7~deb10u3+rpi1), libmatroska6v5:armhf (1.4.9-1, 1.4.9-1+deb10u1), systemd:armhf (241-7~deb10u2+rpi1, 241-7~deb10u3+rpi1), libwebkit2gtk-4.0-37:armhf (2.26.3-1~deb10u1+rpi1, 2.26.4-1~deb10u1+rpi1), libqt5core5a:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), piwiz:armhf (0.8, 0.9), libraspberrypi0:armhf (1.20200114-1, 1.20200212-1), openssh-server:armhf (1:7.9p1-10+deb10u1, 1:7.9p1-10+deb10u2), openssh-client:armhf (1:7.9p1-10+deb10u1, 1:7.9p1-10+deb10u2), libmysofa0:armhf (0.6~dfsg0-3, 0.6~dfsg0-3+deb10u1), rpi-chromium-mods:armhf (20200124, 20200207), binutils-common:armhf (2.31.1-16+rpi1, 2.31.1-16+rpi2), rp- prefapps:armhf (0.15, 0.17), libqt5opengl5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), libmariadb3:armhf (1:10.3.17-0+deb10u1, 1:10.3.22-0+deb10u1), libfm-data:armhf (1.3.1-1+rpt12, 1.3.1-1+rpt13), libbinutils:armhf (2.31.1-16+rpi1, 2.31.1-16+rpi2), libgnutls30:armhf (3.6.7-4, 3.6.7-4+deb10u2), libqt5network5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), pcmanfm:armhf (1.3.1-1+rpt17, 1.3.1-1+rpt18), libcupsimage2:armhf (2.2.10-6+deb10u1, 2.2.10-6+deb10u2), libgnutls-dane0:armhf (3.6.7-4, 3.6.7-4+deb10u2), libjavascriptcoregtk-4.0-18:armhf (2.26.3-1~deb10u1+rpi1, 2.26.4-1~deb10u1+rpi1), python-pil:armhf (5.4.1-2, 5.4.1-2+deb10u1), libqt5sql5:armhf (5.11.3+dfsg1-1+rpi1, 5.11.3+dfsg1-1+rpi1+deb10u3), docker-ce:armhf (5:19.03.5~3-0~raspbian-buster, 5:19.03.6~3-0~raspbian- buster), base-files:armhf (10.3+rpi1+deb10u2, 10.3+rpi1+deb10u3), docker-ce-cli:armhf (5:19.03.5~3-0~raspbian-buster, 5:19.03.6~3-0 ~raspbian-buster), libfm-gtk-data:armhf (1.3.1-1+rpt12, 1.3.1-1+rpt13) The RPi has had the "turn off IPv6" lines mentioned in earlier comments in sysctl.conf since the machine was first installed. The reason had nothing to do with this kind of problem - I wanted to stop IPv6 DNS requests cluttering-up my PiHole logs and killing IPv6 entirely seemed the best way to do that. My DHCP server is a DrayTek router. It had been set to a 3-day lease time. I've just upped that to 10 days for no particular reason other than earlier postings suggest longer times are better. It's only a home network and I'm hardly going to run out of leases. -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to network-manager in Ubuntu. https://bugs.launchpad.net/bugs/1586528 Title: Avahi-daemon withdraws address record Status in avahi package in Ubuntu: Invalid Status in network-manager package in Ubuntu: Confirmed Bug description: For some reason, if I leave my Ubuntu VM up for a prolonged period of time the machine will lose connection to the network. ip addr shows that the nic port no longer has an address and an examination of the syslog shows this: May 27 14:19:38 matt-VirtualBox avahi-daemon[590]: Withdrawing address record for 10.0.2.15 on enp0s3. May 27 14:19:38 matt-VirtualBox avahi-daemon[590]: Leaving mDNS multicast group on interface enp0s3.IPv4 with address 10.0.2.15. May 27 14:19:38 matt-VirtualBox avahi-daemon[590]: Interface enp0s3.IPv4 no longer relevant for mDNS. for no known reason. The only reliable way to get the network to come back (that I have found) is a full reboot. ProblemType: Bug DistroRelease: Ubuntu 16.04 Package: avahi-daemon 0.6.32~rc+dfsg-1ubuntu2 ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8 Uname: Linux 4.4.0-22-generic x86_64 ApportVersion: 2.20.1-0ubuntu2 Architecture: amd64 CurrentDesktop: Unity Date: Fri May 27 15:11:34 2016 InstallationDate: Installed on 2015-10-22 (218 days ago) InstallationMedia: Ubuntu 15.10 "Wily Werewolf" - Release amd64 (20151021) SourcePackage: avahi UpgradeStatus: Upgraded to xenial on 2016-03-30 (58 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/avahi/+bug/1586528/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp