Dear colleagues, Yesterday, 19 September 2022, between 14:36 and 15:08 clients may have observed an inconsistent state of rrdp.ripe.net. After becoming aware of a potential issue, we mitigated the problem by switching to our secondary RRDP infrastructure before starting our investigation. During the incident, the RRDP repository https://rrdp.ripe.net/notification.xml referred to files that were not available. Out of over 14.5k requests (excluding traffic after failover), 5289 requests resulted in a 404 response. According to our logs and external monitoring, the rsync repository rsync://rpki.ripe.net was fully available during this period, although the service may have been slower than usual due to a high IO load. The trigger of this incident was an automatic failover to a backup publication server, where the primary server recovered in a matter of seconds, which resulted in an automatic switch back. From our logs, we observed that HTTP Keep-Alive kept the CDN connected to the backup server for notification.xml and new connections for snapshot and delta files were made to the primary server. We recognize that this is a similar outage report as the one from 12 September [1], and will continue with fixing these race conditions in our infrastructure. [1] - https://www.ripe.net/ripe/mail/archives/routing-wg/2022-September/004606.htm... Kind regards, Bart Bakker Senior Software Engineer RIPE NCC