This affects bionic openstack cloud environments when os-*-hostname is configured for keystone, and the keystone entry is deleted temporarily from upstream dns, or the upstream dns fails providing no record for the lookup of keystone.endpoint.domain.com.
We have to then flush all caches across the cloud once DNS issue is resolved, rather than auto-healing at 60 seconds as if we were running nscd with negative-ttl set to 60 seconds. Ultimately, a negative TTL that is settable would be ideal, or the ability to not cache negative hits would also be useful. Only workaround now is to not use caches or to operationally flush caches as needed. -- 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/1668771 Title: systemd-resolved negative caching for extended period of time Status in systemd: New Status in systemd package in Ubuntu: Confirmed Bug description: 231-9ubuntu3 If a DNS lookup returns SERVFAIL, systemd-resolved seems to cache the result for very long (infinity?). I have to restart systemd-resolved to have the negative caching purged. After SERVFAIL DNS server issue has been resolved, chromium/firefox still returns DNS error despite host can correctly resolve the name. To manage notifications about this bug go to: https://bugs.launchpad.net/systemd/+bug/1668771/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp
