** Merge proposal linked: https://code.launchpad.net/~smoser/cloud-init/+git/cloud-init/+merge/310547
-- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to dbus 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: Fix Committed Status in D-Bus: Unknown Status in cloud-init package in Ubuntu: Fix Released Status in dbus package in Ubuntu: Won't Fix Status in cloud-init source package in Xenial: Confirmed Status in cloud-init source package in Yakkety: Fix Released Bug description: === Begin SRU Template === [Impact] In cases where cloud-init used dns during early boot and system was configured in nsswitch.conf to use systemd-resolvd, the system would timeout on dns attempts making system boot terribly slow. [Test Case] Boot a system on GCE. check for WARN in /var/log/messages check that time to boot is reasonable (<30 seconds). In failure case the times would be minutes. [Regression Potential] Changing order in boot can be dangerous. There is real chance for regression here, but it should be fairly small as xenial does not include systemd-resolved usage. This was first noticed on yakkety where it did. [Other Info] It seems useful to SRU this in the event that systemd-resolvd is used on 16.04 or the case where user upgrades components (admittedly small use case). === End SRU Template === 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/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
