serial-console excerpt (step [2], join-mount):
hammer2_mount: devstr="/dev/vn1@CLUS"
hammer2_mount: device="/dev/vn1" label="CLUS" rdonly=0
hammer2_ondisk: "/dev/vn1" zone=0 id=0 offset=0x0000000000000000 size=0x0000000040000000
hammer2_mount: "/dev/vn1": no recovery needed
hammer2_mount: hmp=0xfffff801194bc000 pmp=0xfffff80118e20000
hammer2_mount: PFS already mounted!