Description of problem: After installing a Fedora 25 virtual guest on a Fedora 25 host system using the latest live image F25-WORK-x86_64-20170202, network appears to be up and running. After installing all available latest updates, however, and rebooting the virtual machine, name resolution is lost. What is puzzling is that running 'ifconfig' returns a different setup after updating the virtual machine. Right after installing the virtual machine, 'ifconfig' returns: ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.122.179 netmask 255.255.255.0 broadcast 192.168.122.255 inet6 fe80::65d:53cf:7acd:f2bb prefixlen 64 scopeid 0x20<link> ether 52:54:00:96:89:1e txqueuelen 1000 (Ethernet) RX packets 50124 bytes 73813402 (70.3 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 23684 bytes 1436586 (1.3 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 118227 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1 (Local Loopback) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 However, after updating the virtual machine, 'ifconfig' returns: ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.122.179 netmask 255.255.255.0 broadcast 192.168.122.255 inet6 fe80::65d:53cf:7acd:f2bb prefixlen 64 scopeid 0x20<link> ether 52:54:00:96:89:1e txqueuelen 1000 (Ethernet) RX packets 12 bytes 2036 (1.9 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 47 bytes 5729 (5.5 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 138 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1 (Local Loopback) RX packets 160 bytes 11552 (11.2 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 160 bytes 11552 (11.2 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255 ether 52:54:00:01:5c:5f txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 Thus, a virtual bridge is present now which did not exist before. Furthermore, 'dmesg' exhibits some new trailing lines, namely: [ .. ] tun: Universal TUN/TAP device driver, 1.6 [ .. ] tun: (C) 1999-2004 Max Krasnyansky <maxk qualcomm com> [ .. ] virbr0: port 1(virbr0-nic) entered blocking state [ .. ] virbr0: port 1(virbr0-nic) entered disabled state [ .. ] device virbr0-nic entered promiscuous mode [ .. ] virbr0: port 1(virbr0-nic) entered blocking state [ .. ] virbr0: port 1(virbr0-nic) entered listening state [ .. ] virbr0: port 1(virbr0-nic) entered disabled state Version-Release number of selected component (if applicable): gnome-boxes-3.22.4-1.fc25 How reproducible: Always. Steps to Reproduce: 1. Install Fedora 25 in a virtual machine using live image F25-WORK-x86_64-20170202. 2. Update installed virtual machine. Actual results: While it is possible to retrieve pending updates over the network after booting up the new virtual machine, name resolution is broken after rebooting the updated virtual machine. Expected results: Name resolution is working just like in the live session. Additional info: None
Looking at the output of 'ifconfig' in a current Fedora 24 virtual machine, ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.122.161 netmask 255.255.255.0 broadcast 192.168.122.255 inet6 fe80::28d9:ec3:68f3:8791 prefixlen 64 scopeid 0x20<link> ether 52:54:00:48:0b:2a txqueuelen 1000 (Ethernet) RX packets 26834 bytes 22875114 (21.8 MiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 20369 bytes 2690889 (2.5 MiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 100426 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1 (Local Loopback) RX packets 24 bytes 1824 (1.7 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 24 bytes 1824 (1.7 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 inet 192.168.124.1 netmask 255.255.255.0 broadcast 192.168.124.255 ether 00:00:00:00:00:00 txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 Note that the three leading bytes of the IPs of devices 'ens3' (192.168.122.x) and 'virbr0' (192.168.124.x) are different here, whereas under Fedora 25, they are identical (192.168.122.x). In a virtual machine running current Fedora 24, network connectivity is working correctly.
After installing Fedora 25 on a virtual guest using the official live image Fedora-Workstation-Live-x86_64-25-1.3, the installed and updated systems still exibits working name resolution. Two differences compared to the earlier installation using F25-WORK-x86_64-20170202 appear related: (1) The output of 'ifconfig' in the current Fedora 25 virtual machine becomes ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.122.154 netmask 255.255.255.0 broadcast 192.168.122.255 inet6 fe80::a8be:85f0:ff64:e903 prefixlen 64 scopeid 0x20<link> ether 52:54:00:42:86:27 txqueuelen 1000 (Ethernet) RX packets 82 bytes 10957 (10.7 KiB) RX errors 0 dropped 13 overruns 0 frame 0 TX packets 105 bytes 10485 (10.2 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1 (Local Loopback) RX packets 24 bytes 1824 (1.7 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 24 bytes 1824 (1.7 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 inet 192.168.124.1 netmask 255.255.255.0 broadcast 192.168.124.255 ether 52:54:00:45:90:38 txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 which is equivalent to the situation under Fedora 24. (2) The network device using live image Fedora-Workstation-Live-x86_64-25-1.3 becomes Ethernet controller: Red Hat, Inc Virtio network device whereas using live image F25-WORK-x86_64-20170202, it was Ethernet controller: Realtek Semiconductor Co., Ltd. RTL-8100/8101L/8139 PCI Fast Ethernet Adapter (rev 20)
For the latest live image F25-WORK-x86_64-20170210, things have gotten normal again. After installing Fedora 25 on a virtual machine using the latter and rebooting the system, 'ifconfig' returns: ens3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 192.168.122.8 netmask 255.255.255.0 broadcast 192.168.122.255 inet6 fe80::6c96:cdd6:38b6:b8ce prefixlen 64 scopeid 0x20<link> ether 52:54:00:b3:dc:e3 txqueuelen 1000 (Ethernet) RX packets 47 bytes 5764 (5.6 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 78 bytes 8635 (8.4 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 271 lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536 inet 127.0.0.1 netmask 255.0.0.0 inet6 ::1 prefixlen 128 scopeid 0x10<host> loop txqueuelen 1 (Local Loopback) RX packets 32 bytes 2352 (2.2 KiB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 32 bytes 2352 (2.2 KiB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500 inet 192.168.124.1 netmask 255.255.255.0 broadcast 192.168.124.255 ether 52:54:00:90:49:ce txqueuelen 1000 (Ethernet) RX packets 0 bytes 0 (0.0 B) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 0 bytes 0 (0.0 B) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0