[ale] dd & unexpected soft update inconsistency, HUH ?

[Stephan Uphoff]

On Fri, 2005-04-15 at 09:25, Courtney Thomas wrote:
> I've been using dd for years to mirror my server HD without problems.
> 
> The command used is:	dd if=< original HD > of=< mirror HD >

I don't think dd is a good idea on a life file system ....
...but you probably know this so let's ignore this for now.

> However, yesterday, for the first time, when I do this, I get the error:
> 
> 	UNEXPECTED SOFT UPDATE INCONSISTENCY
> 
> This happens to mirror HD /usr only.
> Mirror HD / and /var do not exhibit this problem.
> 
> If I fsck the mirror HD, all is OK except mirror HD /usr in which I get
> a plethora of errors complaining about soft update inconsistencies.
> 
> If I attempt to examine mirror HD /usr with ls -l, I see there's also a
> raft of BAD FILE DESCRIPTORs.
> 
> Further, the dd completion screen shows... an error coming from the
> original HD, i.e. not the mirrored HD, drive. It only reports "[original
> HD] input error". But when I fsck all partitions of that original HD,
> all is reported as satisfactory.

Looks like you have a bad sector somewhere on the disk.
Is there something in the log file?
The /usr partition is probably only partially copied.

You can try the following:
1) tar up /usr so that all used data blocks will be read.
   This may indicate an unreadable file .. or you may be lucky and the
bad sector is in unused space.
2) Locate the defect sector (dd to /dev/null with offset,counts...)
3) Write zeroes to the defect sector to "repair" it and fsck..
4) Restore the file that was not readable in 1)	           

I believe that there are disk repair tools in the ports tree but never
had the need to try them.

> What's goin' on here and how can I remedy it. This is my gateway server
> and I urgently need to resolve this.
> 
> Appreciatively,
> 
> Courtney
> 
> 
> 
> _______________________________________________
> Ale mailing list
> Ale at ale.org
> http://www.ale.org/mailman/listinfo/ale
> 
>