On Tue, May 2, 2017 at 8:54 AM, Dimitri John Ledkov <launch...@surgut.co.uk> wrote:
> Ideally, the following should happen: > * boot > * Created link configuration context > <netplan creates/changes .link files to have a new MTU setting> > * Check if link configuration needs reloading -> appears in the debug logs > * New MTU is successfully applied > Let me put in the cloud-init sequence and see if we can figure out what may be missing. * boot * systemd-udev* sockets, trigger, settle, udevd , cloud-init-local : run * cloud-init writes a netplan.yaml * cloud-init invokes netplan-generate * system reaches sysinit.target Looking at the deps on the systemd-udev units; there's no strict ordering in cloud-init that says it would run before, or strictly after udev related units. If you note about the ignoring updated files that are less than 3 seconds old as well as systemd's variability w.r.t unit ordering due to missing explicit Before/After directives might explain the race. I'd prefer not to wait for 3 seconds just because; so it maybe use useful to see if we can run cloud-init before udev; however it's not clear if invoking udev settle in cloudinit (which is done at various places directly (or indirectly through calling programs like blkid or other system programs) would end up waiting. We could also explicitly order cloud-init-local after the udevd service which depends on all other udev units; however, if cloud-init runs immediately after it, the 3 seconds may not have passed. I like running after udevd, but I would like to see if we can force/configure udev to not wait that 3 seconds; > If the 'Check ...' is missing from the debug logs, after netplan has > run, udevd will not reload the configs. > > I also would have thought that calling udevadm control --reload would > force it to reload the contexts for the builtins. > > >From the original bug report description there is a call to: > 'systemctl', 'start', '--no-block', 'systemd-udev-trigger.service' > > But if one is doing that, to avoid races, one should call udevadm settle > -t 3 before re-triggering add. > Note that -t 3, --timeout=3 only sets the maxium wait time; this means that if it processes any event with in those 3 seconds, that we may not have waited long enough for udev when it re-reads link files and says it's not 3 seconds since the last time. The 3 second re-read is arbitrary and ideally should be replaced by content hashing or use of inotify such that changes to the file (.link) can be triggered automatically without hacky things like sleep 3. > These things are possibly red herrings too. > > -- > You received this bug notification because you are subscribed to the bug > report. > https://bugs.launchpad.net/bugs/1669564 > > Title: > udevadm trigger subsystem-match=net doesn't always run rules > > To manage notifications about this bug go to: > https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/ > 1669564/+subscriptions > -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to systemd in Ubuntu. https://bugs.launchpad.net/bugs/1669564 Title: udevadm trigger subsystem-match=net doesn't always run rules Status in systemd package in Ubuntu: New Bug description: 1. root@ubuntu:~# lsb_release -rd Description: Ubuntu Zesty Zapus (development branch) Release: 17.04 2. root@ubuntu:~# apt-cache policy udev udev: Installed: 232-18ubuntu1 Candidate: 232-18ubuntu1 Version table: *** 232-18ubuntu1 500 500 http://archive.ubuntu.com/ubuntu zesty/main amd64 Packages 100 /var/lib/dpkg/status 3. udevadm trigger --verbose --subsystem-match=net --action=add will run and read .link files from /run/systemd/network/10-netplan-interface1.link and apply MTU settings 4. during system boot running (3) does not set the MTU; running (3) after boot has completed MTU is set correctly. Here'a log during boot where cloud-init generates a netplan config, invokes `netplan generate` which writes the networkd config out and then udevadm trigger (3). Upon logging in interface1 has an MTU of 1500. Re-running udevadm trigger now runs the rules/link files and updates the MTU. Note that, if you run udevadm test /sys/class/net/interface1; this also will apply the MTU (test probably shouldn't change the interface, I'll file a bug for that as well). # journalctl -o short-precise --no-pager -b | grep WARK Mar 02 19:17:19.839797 ubuntu cloud-init[647]: WARK: ['netplan', '--debug', 'generate']: Mar 02 19:17:19.839797 ubuntu cloud-init[647]: WARK: ['stat', '/run/systemd/network/10-netplan-interface1.link']: Mar 02 19:17:19.839797 ubuntu cloud-init[647]: WARK: ['cat', '/run/systemd/network/10-netplan-interface1.link']: Mar 02 19:17:19.839797 ubuntu cloud-init[647]: WARK: ['systemctl', 'start', '--no-block', 'systemd-udev-trigger.service']: Mar 02 19:17:19.839797 ubuntu cloud-init[647]: WARK: ['udevadm', 'trigger', '--verbose', '--subsystem-match=net', '--action=add']: root@ubuntu:~# cat /run/systemd/network/10-netplan-interface1.link [Match] MACAddress=52:54:00:12:34:02 [Link] Name=interface1 WakeOnLan=off MTUBytes=1492 root@ubuntu:~# ifconfig interface1 interface1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500 inet 10.0.2.100 netmask 255.255.255.0 broadcast 10.0.2.255 inet6 fe80::5054:ff:fe12:3402 prefixlen 64 scopeid 0x20<link> inet6 fec0::5054:ff:fe12:3402 prefixlen 64 scopeid 0x40<site> ether 52:54:00:12:34:02 txqueuelen 1000 (Ethernet) RX packets 16 bytes 5053 (5.0 KB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 35 bytes 3287 (3.2 KB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 root@ubuntu:~# udevadm trigger --verbose --subsystem-match=net --action=add /sys/devices/pci0000:00/0000:00:04.0/virtio1/net/interface1 /sys/devices/pci0000:00/0000:00:05.0/virtio2/net/interface2 ys/devices/pci0000:00/0000:00:06.0/virtio3/net/interface0 /sys/devices/virtual/net/lo root@ubuntu:~# ifconfig interface1 interface1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1492 inet 10.0.2.100 netmask 255.255.255.0 broadcast 10.0.2.255 inet6 fe80::5054:ff:fe12:3402 prefixlen 64 scopeid 0x20<link> inet6 fec0::5054:ff:fe12:3402 prefixlen 64 scopeid 0x40<site> ether 52:54:00:12:34:02 txqueuelen 1000 (Ethernet) RX packets 16 bytes 5053 (5.0 KB) RX errors 0 dropped 0 overruns 0 frame 0 TX packets 37 bytes 3504 (3.5 KB) TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0 ProblemType: Bug DistroRelease: Ubuntu 17.04 Package: udev 232-18ubuntu1 ProcVersionSignature: Ubuntu 4.10.0-8.10-generic 4.10.0-rc8 Uname: Linux 4.10.0-8-generic x86_64 ApportVersion: 2.20.4-0ubuntu2 Architecture: amd64 Date: Thu Mar 2 19:22:14 2017 Lsusb: Error: command ['lsusb'] failed with exit code 1: MachineType: QEMU Standard PC (i440FX + PIIX, 1996) ProcEnviron: TERM=vt220 PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_US.UTF-8 SHELL=/bin/bash ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.10.0-8-generic root=UUID=8bbb84fe-91e8-4a9a-bd91-f6af4793727e ro console=ttyS0 SourcePackage: systemd UpgradeStatus: No upgrade log present (probably fresh install) dmi.bios.date: 04/01/2014 dmi.bios.vendor: SeaBIOS dmi.bios.version: 1.10.1-1ubuntu1 dmi.chassis.type: 1 dmi.chassis.vendor: QEMU dmi.chassis.version: pc-i440fx-zesty dmi.modalias: dmi:bvnSeaBIOS:bvr1.10.1-1ubuntu1:bd04/01/2014:svnQEMU:pnStandardPC(i440FX+PIIX,1996):pvrpc-i440fx-zesty:cvnQEMU:ct1:cvrpc-i440fx-zesty: dmi.product.name: Standard PC (i440FX + PIIX, 1996) dmi.product.version: pc-i440fx-zesty dmi.sys.vendor: QEMU To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1669564/+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
