> > > On 1/11/23 02:09, Simon Matter wrote: >>> I plan to upgrade an existing C7 computer which currently has one 256 >>> GB >>> SSD to use mdadmin software RAID1 after adding two 4 TB M2. SSDs, the >>> rest >>> of the system remaining the same. The system also has one additional >>> internal and one external harddisk but these should not be touched. The >>> system will continue to run C7. > .... trimming >>> >>> - I do not see any benefit to breaking up the LVM2/LUKS partition >>> containing /root, /swap and /home into more than one RAID1 partition or >>> am >>> I wrong? If the SSD fails, the entire SSD would fail and break the >>> system, >>> hence I might as well keep it as one single RAID1 partition, or? >> What I usually do is this: "cut" the large disk into several pieces of >> equal size and create individual RAID1 arrays. Then add them as LVM PVs >> to >> one large VG. The advantage is that with one error on one disk, you wont >> lose redundancy on the whole RAID mirror but only on a partial segment. >> You can even lose another segment with an error on the other disk and >> still have redundancy if the error is in another part. >> >> That said, it's a bit more work to setup but has helped me several times >> in the decades ago. > > Ah, now I begin to get it. Separate partitions RAIDed. Yes, exactly, sorry for not being clear enough. The structure of disk 0 looks like this: $ lsblk -o NAME,FSTYPE,SIZE,MOUNTPOINT /dev/nvme0n1 NAME FSTYPE SIZE MOUNTPOINT nvme0n1 745.2G ├─nvme0n1p1 vfat 200M /boot/efi ├─nvme0n1p2 linux_raid_member 1G │ └─md0 xfs 1023M /boot ├─nvme0n1p3 linux_raid_member 186G │ └─md1 LVM2_member 185.9G │ ├─main-root xfs 30G / │ ├─main-swap swap 16G [SWAP] │ ├─main-tmp xfs 10G /tmp │ ├─main-var xfs 200G /var │ └─main-imap xfs 1.2T /var/spool/imap ├─nvme0n1p4 linux_raid_member 186G │ └─md2 LVM2_member 185.9G │ └─main-imap xfs 1.2T /var/spool/imap ├─nvme0n1p5 linux_raid_member 186G │ └─md3 LVM2_member 185.9G │ └─main-imap xfs 1.2T /var/spool/imap ├─nvme0n1p6 linux_raid_member 186G │ └─md4 LVM2_member 185.9G │ ├─main-var xfs 200G /var │ └─main-imap xfs 1.2T /var/spool/imap └─nvme0n1p7 15.8M Regards, Simon