ZFS - Pools - Check Status of a ZFS Pool

zpool status -v testpool

returns:

  pool: testpool
 state: ONLINE
  scan: scrub repaired 0B in 21:37:28 with 0 errors on Sun Nov 15 21:37:28 2020
config:
 
	NAME                                            STATE     READ WRITE CKSUM
	testpool                                        ONLINE       0     0     0
	  raidz1-0                                      ONLINE       0     0     0
	    gptid/2d35e96c-b611-11ea-be33-00d861fcb7d8  ONLINE       0     0     0
	    gptid/2d41dcbd-b611-11ea-be33-00d861fcb7d8  ONLINE       0     0     0
	    gptid/2ddb5cb2-b611-11ea-be33-00d861fcb7d8  ONLINE       0     0     0
 
errors: No known data errors

Pool Status Definitions

The overall health of a pool, as reported by zpool status, is determined by the aggregate state of all devices within the pool.

Pool Status	Definition
ONLINE	All devices can (and should while operating optimally) be in the ONLINE state. This includes the pool, top-level VDEVs (parity groups of type mirror, raidz{1,2,3}) and the drives themselves. Transitory errors may still occur without the drive changing state.
OFFLINE	Only bottom-level devices (drives) can be OFFLINE. This is a manual administrative state, and healthy drives can be brought back online and active into the pool.
UNAVAIL	The device (or VDEV) in question can not be opened. If a VDEV is UNAVAIL, the pool will not be accessible or able to be imported. UNAVAIL devices may also report as FAULTED in some scenarios. Operationally, UNAVAIL disks are roughly equivalent to FAULTED disks.
DEGRADED	A fault in a device has occurred, impacting all VDEVs above it. The pool is still operable, but redundancy may have been lost in a VDEV.
REMOVED	The device was physically removed while the system was running. Device removal detection is hardware-dependent and might not be supported on all platforms.
FAULTED	All components (top and redundancy VDEVs, and drives) of the pool can be in a FAULTED state. A FAULTED component is completely inaccessible. The severity of a device being DEGRADED depends a lot on which device it is.
INUSE	This is a status reserved for spares which have been used to replace a faulted drive.