I really think you are all *way* over thinking this. a. growpart made a change to the partition table (using sfdisk) b. growpart called partx --update --nr 3 /dev/sda c. growpart exited
With a and b growpart created udev events. If you create udev events, you really need to wait for those events to finish, or your just pushing complexity onto your consumer. Now Daniel's updated cloud-init with output captured in comment 14 clearly called udevadm settle after 'c'. But the problem still existed. So that means we have this sequence of events: a.) growpart change partition table b.) growpart call partx c.) udev created and events being processed d.) growpart exits e.) cloud-init calls udevadm settle f.) udev events occurring that removed the link g.) cloud-init raced on reading that size - fail To me, that means either udevadm settle called in 'e' didn't actually do what it is suppsoed to do and wait for all events in the queue to clear. Or, something else created new events. I have long suspected that to be the case, and I think the thing doing it is udev rules. If that is true, then udev events cause more udev events, so a single 'settle' is never enough. Nor can you actually ever know if you *have* settled long enough. -- 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/1834875 Title: cloud-init growpart race with udev Status in cloud-init: Incomplete Status in cloud-utils: New Status in linux-azure package in Ubuntu: New Status in systemd package in Ubuntu: Incomplete Bug description: On Azure, it happens regularly (20-30%), that cloud-init's growpart module fails to extend the partition to full size. Such as in this example: ======================================== 2019-06-28 12:24:18,666 - util.py[DEBUG]: Running command ['growpart', '--dry-run', '/dev/sda', '1'] with allowed return codes [0] (shell=False, capture=True) 2019-06-28 12:24:19,157 - util.py[DEBUG]: Running command ['growpart', '/dev/sda', '1'] with allowed return codes [0] (shell=False, capture=True) 2019-06-28 12:24:19,726 - util.py[DEBUG]: resize_devices took 1.075 seconds 2019-06-28 12:24:19,726 - handlers.py[DEBUG]: finish: init-network/config-growpart: FAIL: running config-growpart with frequency always 2019-06-28 12:24:19,727 - util.py[WARNING]: Running module growpart (<module 'cloudinit.config.cc_growpart' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py'>) failed 2019-06-28 12:24:19,727 - util.py[DEBUG]: Running module growpart (<module 'cloudinit.config.cc_growpart' from '/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py'>) failed Traceback (most recent call last): File "/usr/lib/python3/dist-packages/cloudinit/stages.py", line 812, in _run_modules freq=freq) File "/usr/lib/python3/dist-packages/cloudinit/cloud.py", line 54, in run return self._runners.run(name, functor, args, freq, clear_on_fail) File "/usr/lib/python3/dist-packages/cloudinit/helpers.py", line 187, in run results = functor(*args) File "/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py", line 351, in handle func=resize_devices, args=(resizer, devices)) File "/usr/lib/python3/dist-packages/cloudinit/util.py", line 2521, in log_time ret = func(*args, **kwargs) File "/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py", line 298, in resize_devices (old, new) = resizer.resize(disk, ptnum, blockdev) File "/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py", line 159, in resize return (before, get_size(partdev)) File "/usr/lib/python3/dist-packages/cloudinit/config/cc_growpart.py", line 198, in get_size fd = os.open(filename, os.O_RDONLY) FileNotFoundError: [Errno 2] No such file or directory: '/dev/disk/by-partuuid/a5f2b49f-abd6-427f-bbc4-ba5559235cf3' ======================================== @rcj suggested this is a race with udev. This seems to only happen on Cosmic and later. To manage notifications about this bug go to: https://bugs.launchpad.net/cloud-init/+bug/1834875/+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