Short answer: no and no.
Long:
1. having size = 2 is safe *if you also keep min_size at 2*. But
that's not highly available so you usually don't want this. min_size =
1 (or reducing min size on an ec pool) is basically a guarantee to
lose at least some data/writes in the long run.
2. It's no
"when using BlueStore, Ceph can ensure data integrity by conducting a cyclical
redundancy check (CRC) on write operations; then, store the CRC value in the
block database. On read operations, Ceph can retrieve the CRC value from the
block database and compare it with the generated CRC of the
