I'm sorry to report that I got a new problem, I was executing a zfs recv of a few GBs of data while, at the same time, executing a dd if=/dev/zero of=/... onto my test pool, which right now has 4 disks in two mirror vdevs, when the pool stopped responding.

Feb 9 19:38:54 pg-1 ipmi: [ID 183295 kern.info] SMBIOS type 0x1, addr 0xca2

Feb 9 19:38:54 pg-1 ipmi: [ID 306142 kern.info] device rev. 3, firmware rev. 2.65, version 2.0

Feb 9 19:38:54 pg-1 ipmi: [ID 935091 kern.info] number of channels 2

Feb 9 19:38:54 pg-1 ipmi: [ID 699450 kern.info] watchdog supported

Feb 9 19:38:55 pg-1 scsi: [ID 583861 kern.info] ses0 at lmrc2: target-port w300162b20dde3640 lun 0

Feb 9 19:38:55 pg-1 genunix: [ID 936769 kern.info] ses0 is /pci@0,0/pci8086,43b8@1c/pci1590,32b@0/iport@p0/enclosure@w300162b20dde3>

Feb 9 19:42:05 pg-1 fmd: [ID 377184 daemon.error] SUNW-MSG-ID: ZFS-8000-GH, TYPE: Fault, VER: 1, SEVERITY: Major#012EVENT-TIME: Fri>

Feb 9 19:51:46 pg-1 rootnex: [ID 349649 kern.info] xsvc0 at root: space 0 offset 0

Feb 9 19:51:46 pg-1 genunix: [ID 936769 kern.info] xsvc0 is /xsvc@0,0

Feb 10 08:24:08 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 08:24:16 pg-1 lmrc: [ID 998901 kern.warning] WARNING: lmrc0: AEN failed, status = 255

Feb 10 08:24:16 pg-1 lmrc: [ID 831201 kern.warning] WARNING: lmrc0: PD map sync failed, status = 255

Feb 10 08:24:17 pg-1 zfs: [ID 961531 kern.warning] WARNING: Pool 'dati' has encountered an uncorrectable I/O failure and has been su>

Feb 10 08:24:22 pg-1 lmrc: [ID 864919 kern.notice] NOTICE: lmrc0: FW is in fault state!

Feb 10 08:24:22 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 08:28:02 pg-1 fmd: [ID 377184 daemon.error] SUNW-MSG-ID: ZFS-8000-FD, TYPE: Fault, VER: 1, SEVERITY: Major#012EVENT-TIME: Sat>

Feb 10 08:28:03 pg-1 fmd: [ID 377184 daemon.error] SUNW-MSG-ID: ZFS-8000-FD, TYPE: Fault, VER: 1, SEVERITY: Major#012EVENT-TIME: Sat>

Feb 10 08:28:10 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 08:28:18 pg-1 lmrc: [ID 380853 kern.warning] WARNING: lmrc0: LD target map sync failed, status = 255

Feb 10 08:34:49 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 08:41:27 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 08:48:06 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 08:54:45 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 09:01:24 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 09:08:03 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 09:14:42 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

Feb 10 09:21:21 pg-1 lmrc: [ID 408335 kern.warning] WARNING: lmrc0: resetting...

and it was still trying to reset it this morning, iostat -indexC shows this

r/s w/s kr/s kw/s wait actv wsvc_t asvc_t %w %b s/w h/w trn tot device

0.0 61.1 0.0 325.8 0.0 0.0 0.0 0.4 0 3 0 0 0 0 c2t3d0

0.0 62.1 0.0 325.8 0.0 0.0 0.0 0.2 0 1 0 0 0 0 c2t4d0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 0 0 0 0 c3t001B448B4A7140BFd0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 0 0 24 24 c4t50014EE6B2513C38d0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 0 0 24 24 c4t5000CCA85EE5ECB0d0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 0 0 18 18 c4t5000C500AAF9B0C3d0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 0 0 50 50 c4t5000C500AAF9BF2Fd0

0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0 0 0 0 0 0 c5tACE42E0005CFF480d0

0.0 119.3 0.0 651.6 0.4 0.0 3.3 0.3 3 3 0 0 0 0 rpool

here the pool configuration where the problem occurred

scan: scrub repaired 0 in 0 days 00:53:43 with 0 errors on Fri Feb 9 19:03:47 2024

So I forced a reboot with a dump, which you can find here: