We are an IT company and recently set up a server for a client using an Apple Silicon Mac mini M1, LaCie storage and two external 12 TB Western Digital Elements drives for local backups. These drives are connected to the Mac using USB-A. Hard disk and computer sleep are switched off.
Looking through the logs of the Mac we encountered numerous I/O errors on all these Western Digital Elements drives. We replaced one of them but macOS still logs errors. We tried all three drives separately. Theoretically all three drives could be defective but I find that unlikely.
We then created or own setup using an Apple Silicon Mac mini and an older 3 TB Western Digital Elements and encountered the same type of errors in the system’s log.
Is there a known problem between an Apple Silicon Mac running macOS 26.5 and Western Digital Elements disks?
Ernst Mulder
GrafiSIS & AdvieSIS
Below part of the log, extracted using the log command, grepped for I/O error:
2026-05-20 09:28:22.805959+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIArchitectureModelFamily) [Elements 25A3] I/O error! Opcode 0x8A, Service response 0x02, Task status 0x02, Sense Data 0x02, 0x04, 0x01
2026-05-20 09:28:22.805962+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x2 lba 0x25b2b7698 count 0x8, retry 1 …
2026-05-20 09:28:24.806038+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIArchitectureModelFamily) [Elements 25A3] I/O error! Opcode 0x2A, Service response 0x02, Task status 0x02, Sense Data 0x02, 0x04, 0x01
2026-05-20 09:28:24.806040+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x2 lba 0xf6c88 count 0x20, retry 1 …
2026-05-20 09:28:26.806081+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x2 lba 0xf6ca8 count 0x18, retry 1 …
2026-05-20 09:28:28.806044+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x2 lba 0xf6db8 count 0x10, retry 1 …
2026-05-20 09:28:30.806091+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x2 lba 0xf6dd0 count 0x8, retry 1 …
2026-05-20 10:08:31.468486+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIArchitectureModelFamily) [Elements 25A3] I/O error! Opcode 0x2A, Service response 0x02, Task status 0x02, Sense Data: 0x02, 0x04, 0x01, happened 4 times
2026-05-20 10:08:31.468503+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIArchitectureModelFamily) [Elements 25A3] I/O error! Opcode 0x28, Service response 0x02, Task status 0x02, Sense Data 0x02, 0x04, 0x01
2026-05-20 10:08:31.468515+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x1 lba 0x4946e18 count 0x8, retry 1 …
2026-05-20 10:08:33.469413+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x1 lba 0x4946e18 count 0x8, retry 2 …
2026-05-20 10:08:35.470483+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x1 lba 0x4946e18 count 0x8, retry 3 …
2026-05-20 10:08:38.471538+0200 0x5dc Default 0x0 0 0 kernel: (IOSCSIBlockCommandsDevice) [Elements 25A3]: I/O error [0xe00002d8] dir 0x1 lba 0x4946e18 count 0x8, retry 4 …
