We use Ksplice and KernelCare rebootless kernel updates. However, some servers will be manually upgraded, which requires a reboot. This can take up to 15 minutes. Generally speaking, the ram data is saved to disk and the VPS resumes on startup and appears not to have rebooted.
The maintenance window will be from 12 AM - 12 PM CEST (19th November 2017). However, the downtime for individual VPS will be around 5-10 minutes.
Saturday, November 18, 2017