I'm running -current, on a i386.

Since some days, i've noticed following messages (output from
'dmesg'):

/-----------------
| wd1a: uncorrectable data error reading fsbn 997616 of 997616-997743
| (wd1 bn 997679; cn 989 tn 12 sn 11), retrying 
| wd1a: uncorrectable data error reading fsbn 997616 of 997616-997743
| (wd1 bn 997679; cn 989 tn 12 sn 11), retrying 
| wd1a: uncorrectable data error reading fsbn 997616 of 997616-997743
| (wd1 bn 997679; cn 989 tn 12 sn 11), retrying 
| wd1: transfer error, downgrading to Ultra-DMA mode 2
| wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5 (Ultra/100)
| (using DMA data transfers) 
| wd1(pciide0:0:1): using PIO mode 4, Ultra-DMA mode 2 (Ultra/33) (using
| DMA data transfers) 
| wd1a: uncorrectable data error reading fsbn 997616 of 997616-997743
| (wd1 bn 997679; cn 989 tn 12 sn 11), retrying 
| wd1a: uncorrectable data error reading fsbn 997655 of 997616-997743
| (wd1 bn 997718; cn 989 tn 12 sn 50), retrying 
| wd1a: uncorrectable data error reading fsbn 997655 of 997616-997743
| (wd1 bn 997718; cn 989 tn 12 sn 50) 
| wd1: transfer error, downgrading to Ultra-DMA mode 1
| wd0(pciide0:0:0): using PIO mode 4, Ultra-DMA mode 5 (Ultra/100)
| (using DMA data transfers) 
| wd1(pciide0:0:1): using PIO mode 4
| wd1a: uncorrectable data error reading fsbn 997648 of 997648-997663
| (wd1 bn 997711; cn 989 tn 12 sn 43), retrying 
| wd1a: uncorrectable data error reading fsbn 997648 of 997648-997663
| (wd1 bn 997711; cn 989 tn 12 sn 43), retrying 
| wd1a: uncorrectable data error reading fsbn 997655 of 997648-997663
| (wd1 bn 997718; cn 989 tn 12 sn 50), retrying 
| wd1a: uncorrectable data error reading fsbn 997655 of 997648-997663
| (wd1 bn 997718; cn 989 tn 12 sn 50) 
| wd1a: uncorrectable data error reading fsbn 997648 of 997648-997663
| (wd1 bn 997711; cn 989 tn 12 sn 43), retrying 
| wd1a: uncorrectable data error reading fsbn 997648 of 997648-997663
| (wd1 bn 997711; cn 989 tn 12 sn 43), retrying 
\-----------------

As you may notice, they're always on wd1a, on the same location (i'm
afraid i'm not sure of what fsbn/bn/cn/tn/sn mean). Any advices one
the possible reasons of such messages ?

If it helps:

/-----------------
| pciide0 at pci0 dev 7 function 1: VIA Technologies VT82C686A (Apollo
| KX133) ATA1 100 controller 
| pciide0: bus-master DMA support present
| pciide0: primary channel configured to compatibility mode
| wd0 at pciide0 channel 0 drive 0: <IBM-DTLA-307045>
| (...)
| wd1 at pciide0 channel 0 drive 1: <ST320420A>
\-----------------


When i first install NetBSD, i've already FreeBSD/Solaris/Win on wd0
so i add a second disk to install Net. Now, i've deactivate wd0 in
the BIOS and i boot on wd1. 

/-----------------
| $ mount  
| /dev/wd1a on / type ffs (local, soft dependencies)
| /dev/wd1e on /usr type ffs (local, soft dependencies)
| /dev/wd0g on /freebsd type ffs (local, soft dependencies)
| kernfs on /kern type kernfs (local)
| mfs:124 on /tmp type mfs (asynchronous, local)
\-----------------


My ~/Travail directory is a link to my
old rep, on the FreeBSD slice (/freebsd/jaco/Travail/).

I know this config seems messy (and, sure, it is a shame...;-): in
fact, i should probably nuke my FreeBSD slice and move my NetBSD on
the fatest disk wd0 but i don't figure how to do so the easiest way
(without nuking my current system...).

-- 
Éric Jacoboni, né il y a 1314822666 secondes