What are “UDMA ICRC\ errors, and how do I fix them?
The ata(4) driver reports “UDMA ICRC” errors when a DMA transfer to or from a drive is corrupted. The driver will retry the operation a few times. Should the retries fail, it will switch from DMA to the slower PIO mode of communication with the device. The problem can be caused by many factors, although perhaps the most common cause is faulty or incorrect cabling. Check that the ATA cables are undamaged and rated for the Ultra DMA mode in use. If you’re using removable drive trays, they must also be compatible. Be sure that all connections are making good contact. Problems have also been noticed when an old drive is installed on the same ATA channel as an Ultra DMA 66 (or faster) drive. Lastly, these errors can indicate that the drive is failing. Most drive vendors provide testing software for their drives, so test your drive, and, if necessary, back up your data and replace it. The atacontrol(8) utility can be used to show and select the DMA or PIO modes used for each ATA device. In
