Add a `Disconnect` option for network interfaces on LXC containers, much like it already exists for VMs. This has been requested in #3413 [0] and seems useful, especially considering we already support the same thing for VMs.
One thing to note is that LXC does not seem to support the notion of setting an interface down. The `flags` property would suggest that this possible [1], but AFAICS it does not work. I tried setting the value as empty and to something else than "up" (since that is really the only supported option [2][3]), which both had absolutely no effect. Thus force the host-side link of the container network down and avoid adding it to the designated bridge if the new option is set, effectively disconnecting the container network. The first patch is cleanup only and does not change anything regarding functionality. Testing ------- Testing was done by starting a LXC container (w/ and w/o `link_down` set), checking if the interface has (or not) LOWERLAYERDOWN set inside the container (`ip address eth0`) and if packet transit works (or not) using a simple `ping`. Same thing after toggeling the option on the interface. Further, the interface(s) should (or should not) be listed in `brctl show`. Same thing was done for hotplugged interfaces to a running container. Also tested with `ifreload -a` (thanks Wolfgang!) thrown in, which did nothing unexpected: If `link_down` was set, interfaces stayed in LOWERLAYERDOWN and unplugged from the bridge, and stayed UP and plugged into the bridge when `link_down` was unset. [0] https://bugzilla.proxmox.com/show_bug.cgi?id=3413 [1] https://linuxcontainers.org/lxc/manpages/man5/lxc.container.conf.5.html#lbAO [2] https://github.com/lxc/lxc/blob/08f0e769/src/lxc/confile.c#L453-L467 [3] https://github.com/lxc/lxc/blob/08f0e769/src/lxc/confile.c#L5933-L5952 v1: https://lists.proxmox.com/pipermail/pve-devel/2023-February/055762.html v2: https://lists.proxmox.com/pipermail/pve-devel/2023-February/055795.html v3: https://lists.proxmox.com/pipermail/pve-devel/2023-February/055839.html pve-container: Christoph Heiss (2): net: Pass network config directly to net_tap_plug() net: Add `link_down` config to allow setting interfaces as disconnected src/PVE/LXC.pm | 37 +++++++++++++++++++++++-------------- src/PVE/LXC/Config.pm | 6 ++++++ src/lxcnetaddbr | 9 +-------- 3 files changed, 30 insertions(+), 22 deletions(-) pve-manager: Christoph Heiss (1): lxc: Add `Disconnect` option for network interfaces www/manager6/Parser.js | 3 +++ www/manager6/lxc/Network.js | 13 +++++++++++++ 2 files changed, 16 insertions(+) -- 2.39.1 _______________________________________________ pve-devel mailing list pve-devel@lists.proxmox.com https://lists.proxmox.com/cgi-bin/mailman/listinfo/pve-devel