2018-07-14 Hard disk problems on the home server. :-( I decided to not fiddle long, but to simply throw money at the problem and insert two new disks (the same 3TB disks). Useful information: How to replace disks in a RAID (GPT version): [0] How to make a 2-device RAID 1 a 3-device RAID 1: [1] How to start the resync of a newly re-assembled device: [2] How to work with spares: [3] [0] https://www.howtoforge.com/tutorial/linux-raid-replace- failed-harddisk/ [1] https://lists.debian.org/debian-user/2015/04/msg00761.html [2] https://unix.stackexchange.com/questions/101072/new-md- array-is-auto-read-only-and-has-resync-pending [3] https://unix.stackexchange.com/questions/306286/how-to- mark-one-of-raid1-disks-as-a-spare-mdadm/306291#306291 http://marmaro.de/lue/ markus schnalke