I was creating an LVM RAID 10 across 4 physical volumes (each 3TB) when I got the following error message:
WARNING: New raid10 won't be synchronised. Don't read what you didn't write!
My googling came up with nothing about what this means. Does this mean that the mirroring of the raid will not work and if a single drive fails, all the data is lost?
It's just a warning since you have used option --nosync.
From The man page of lvcreate.
"Specifying the optional argument --nosync will cause the creation of the mirror to skip the initial resynchronization. Any data written afterwards will be mirrored, but the original contents will not be copied. This is useful for skipping a potentially long and resource intensive initial sync of an empty device."