How To Create Software Raid 10 (Raid 1+0) From OS Install.
RAID 10 is designed to offer superior resilience and speed than other RAID levels, as it combines the mirroring protection of RAID 1 with the performance enhancements that RAID 0 offers.
Reset and reformat all disk.
From the first disk put 1Gb in /boot .
leave unformatted the same number of GB on each partition and press create software RAID (md)
Select the “Create software RAID (“MD”)” button to open the creation dialog. The server installer supports creating devices with RAID level 10→ select all disk → press create.
From md0 free space create the partitions ass needed or required.
Press done and continue the installation.