A convenient way to test this is to install libnss-resolve and cloud- init into a yakkety container. Then cloud-init will basically hang forever, looping on
2016-10-04 12:58:48,716 - url_helper.py[WARNING]: Calling 'http://169.254.169.254/2009-04-04/meta-data/instance-id' failed [100/120s]: request error [HTTPConnectionPool(host='169.254.169.254', port=80): Max retries exceeded with url: /2009-04-04/meta-data/instance- id (Caused by NewConnectionError('<requests.packages.urllib3.connection.HTTPConnection object at 0x7f2495137b38>: Failed to establish a new connection: [Errno 113] No route to host',))] and since cloud-init.service runs during early boot, not much else (dbus, resolved, etc.) has started at that time. During that, name resolution is indeed broken. I think nss-resolve should quickly fall back to DNS if D-Bus isn't running yet. ** Changed in: systemd (Ubuntu) Status: New => Triaged -- 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/1629797 Title: resolve service in nsswitch.conf adds 25 seconds to failed lookups before systemd-resolved is up Status in cloud-init package in Ubuntu: Invalid Status in systemd package in Ubuntu: Triaged Bug description: During boot, cloud-init does DNS resolution checks to if particular metadata services are available (in order to determine which cloud it is running on). These checks happen before systemd-resolved is up[0] and if they resolve unsuccessfully they take 25 seconds to complete. This has substantial impact on boot time in all contexts, because cloud-init attempts to resolve three known-invalid addresses ("does- not-exist.example.com.", "example.invalid." and a random string) to enable it to detect when it's running in an environment where a DNS server will always return some sort of redirect. As such, we're talking a minimum impact of 75 seconds in all environments. This increases when cloud-init is configured to check for multiple environments. This means that yakkety is consistently taking 2-3 minutes to boot on EC2 and GCE, compared to the ~30 seconds of the first boot and ~10 seconds thereafter in xenial. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/cloud-init/+bug/1629797/+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
