Dead disk? READ_DMA Failure

Francisco francisco at
Sun Jul 31 14:55:04 GMT 2005

On Fri, 29 Jul 2005, Norbert Koch wrote:

>> I have a one year old Hitachi Travelstar 60GB/4200RPM disk. This
>> night and since then, I get these errors:
>> ad0: TIMEOUT - READ_DMA retrying (2 retries left) LBA=48926527
>> ad0: TIMEOUT - READ_DMA retrying (1 retry left) LBA=48926527
>> ad0: FAILURE - READ_DMA timed out

> I've seen these error messages too. And also WRITE_DMA TIMEOUT!
> You may have a hardware problem, but I'm not convinced.

I don't recall if it was the exact errors, but I had some simmilar ones.
For some reason 5.4 didn't like my ATA100 drive and had to slow down the 
communication speed to the drive.

In my case I added to /usr/local/etc/rc.d a script with

/sbin/atacontrol mode 1 udma66 pio4

Basically slowing down the channel to the drive.. the pio4 is for the 
CDrom and that was it's normal speed.

The drive in question is my backup drive so I only have cron jobs backing 
up to it.. so I didn't mind too much the slowdown.

To view the existing speed of your drive
atacontrol mode 0 (if drive in primary IDE channel)
atacontrol mode 1 (if drive in secondary IDE channel)

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