AMCC 720-0138-00 manual 001E Unit inoperable, 001F Unit Operational, Downgrade Udma mode

Error and Notification Messages

001E Unit inoperable

Drive removal caused a unit to become inoperable. This message is sent after offline unit timer expires (20 seconds); if the unit becomes operational before the timer expires (20 seconds) there will be no message since there were no IO errors.

001F Unit Operational

Drive insertion caused a unit that was inoperable to become operational again. Any data that was on that unit will still be there.This message is sent only after the offline timer expires (20 seconds).

0021 Downgrade UDMA mode

The 3ware RAID controller communicates to the ATA disk drives through the Ultra DMA (UDMA) protocol. This protocol ensures data integrity across the ATA cable by appending a Cyclical Redundancy Check (CRC) for all ATA data that is transferred. If the data becomes corrupted between the drive and the 3ware RAID controller (e.g., an intermittent cable connection) the 3ware RAID controller detects this as a UDMA CRC or cable error. The 3ware RAID controller then retries the failed command three times at the current UDMA transfer rate. If the error persists, it lowers the UDMA transfer rate (e.g., from UDMA 100 to UDMA 66) and retries another three times. This message is sent to you when the 3ware RAID controller lowers the UDMA transfer rate.

Possible causes of UDMA CRC errors are bad interface cables or cable routing problems through electrically noisy environments (e.g., cables are too close to the power supply).

0022 Upgrade UDMA mode

During the self-test, if a drive is found to not be in the optimal UDMA mode, the controller will upgrade its UDMA mode to be optimal.

0023 Sector repair completed

The 3ware RAID controller supports a feature called dynamic sector repair to allow the unit to recover from certain drive errors that would normally result in a degraded unit situation. For redundant units such as RAID 1, 10, and 5, the 3ware RAID controller essentially has two copies of your data available. If a read command to a sector on a disk drive results in an error, it reverts to the redundant copy in order to satisfy the host’s request. At this point, the 3ware RAID controller has a good copy of the requested data in its cache memory. It will then use this data to force the failing drive to reallocate the bad sector, which essentially repairs the sector. When a sector repair occurs, you are notified by this message.

www.3ware.com 121