Package: ifupdown Version: 0.8.36 Severity: important X-Debbugs-Cc: syso...@yandex.ru
Hello! (Not sure why such rather important issue is not filled yet, but anyway. Sorry if I'm creating duplicate.) My network is down after running `systemctl restart networking` on fresh installed Debian 11.5 (but the same issue is on Debian 10). There is no way to start it with `systemctl start networking`. Not sure if this relevant but I'm using static IPv4 config, no DHCP. The installation is very minimal without any systemd-networkd or NetworkManager stuff. The reason for this is that systemd unit file networking.service using `ifdown -a` to stop network and then `ifup -a` to start it. According to the manual, the first command unconditionally deconfigure _all_ interfaces defined in /etc/network/interfaces, but the second one configure only interfaces which is defined as "auto" in the configuraton and not as "allow-hotplug". During the installation all interfaces (fixed PCI NICs too, because udev events generated for PCI devices too [1]) in /etc/network/interfaces is created with "allow-hotplug", so restarting networking with systemd leads to non-functional network. When using old-school `/etc/init.d/networking restart` (don't forget to set SYSTEMCTL_SKIP_REDIRECT=1) the issue is not present. This is because of special treatment for "allow-hotplug" interfaces in /etc/init.d/networking. See ifup_hotplug () function. The functionality is lacking in systemd unit file. Forgot to mention that the network starting normally during the system startup. This is because of ifup@.service template unit which is started from udev rule via /lib/udev/ifupdown-hotplug script which runs unit for specific interface. This leads to running `ifup eth0`. When you run ifup this way, there is no need to define interface as "auto". Yes, everything can be fixed using "auto" instead of "allow-hotplug", but "allow-hotplug" is set by Debian Installer [2]. This leads to the issue just "by default". Should we sync systemd unit file behaviour with old SysV script by implementing something like ifup_hotplug() logic in unit file? Network must not be broken after silly systemctl restart. [1] https://salsa.debian.org/installer-team/hw-detect/-/blob/master/net-hotplug.sh [2] https://salsa.debian.org/installer-team/netcfg/-/blob/master/write_interface.c -- Package-specific info: --- /etc/network/interfaces: # interfaces(5) file used by ifup(8) and ifdown(8) # Include files from /etc/network/interfaces.d: source /etc/network/interfaces.d/* allow-hotplug eth0 iface eth0 inet static address 172.17.0.3 netmask 255.255.0.0 gateway 172.17.0.1 --- /etc/network/interfaces.d/*: cat: '/etc/network/interfaces.d/*': No such file or directory --- up and down scripts installed: /etc/network/if-down.d: total 0 /etc/network/if-post-down.d: total 0 /etc/network/if-pre-up.d: total 0 /etc/network/if-up.d: total 0 -- System Information: Debian Release: 11.5 APT prefers stable-updates APT policy: (500, 'stable-updates'), (500, 'stable-security'), (500, 'stable') Architecture: amd64 (x86_64) Kernel: Linux 5.12.2 (SMP w/1 CPU thread) Kernel taint flags: TAINT_FORCED_MODULE, TAINT_WARN, TAINT_UNSIGNED_MODULE Locale: LANG=C, LC_CTYPE=C.UTF-8 (charmap=UTF-8), LANGUAGE not set Shell: /bin/sh linked to /bin/dash Init: systemd (via /run/systemd/system) Versions of packages ifupdown depends on: ii adduser 3.118 ii iproute2 5.10.0-4 ii libc6 2.31-13+deb11u5 ii lsb-base 11.1.0 Versions of packages ifupdown recommends: ii isc-dhcp-client [dhcp-client] 4.4.1-2.3+deb11u1 Versions of packages ifupdown suggests: pn ppp <none> pn rdnssd <none> -- no debconf information
