[OpenAFS] Re: bos blockscanner

Jason Edgecombe jason@rampaginggeek.com
Sat, 26 Jan 2013 09:42:23 -0500

On 01/26/2013 04:50 AM, Hartmut Reuter wrote:
> When OpenAFS started in 2000 I pushed a lot of extensions into it to make it
> easier to maintain MR-AFS. I think at that time we already were the last site to
> use it. The next years the source code of MR-AFS could be reduced to the very
> specific parts on the server side while with these extensions for all other
> subdirectories simply the openafs code could be used.
> The scanner was a stand alone program which traversed the volume metadata to
> find out which files needed to get a copy elsewhere and which files were
> eligible for wiping (removing from disk). In extreme situations it could be
> helpful to stop the scanner...
> There are many other remains of MR-AFS in different source files of openafs
> which savely could be removed now that MR-AFS is out of service since five years.
> MR-AFS was shutdown finally in 2008. Since than we are running AFS/OSD which has
> a all the features MR-AFS had and some more. I am working on the project to
> bring the AFS/OSD change into the official openafs source code.
> -Hartmut
> Andrew Deason wrote:
>> On Fri, 25 Jan 2013 19:50:41 +0100 (CET)
>> Thorsten Alteholz <openafs@alteholz.de> wrote:
>>> the command 'bos help' says something about 'blockscanner' and
>>> 'unblockscanner'.  This shall start something like
>>> '/usr/afs/bin/scanner -block'. But I did not find anything about such
>>> scanner. Can anybody please shed some light on this? Is this a new
>>> fearture for the future?
>> No, it is very old. I believe that is there to accommodate installations
>> with MR-AFS. MR-AFS is for using AFS with HSM systems but is not freely
>> available or open source or anything; you can google around for what
>> little information exists about it. I'm not sure if it's still in use.
>> Those rpcs hard code the commands they run, ugh...
>> I don't have any familiarity with it, but from what I've seen in the
>> OpenAFS source, I think the 'scanner' process is something that shuffled
>> data between disk and tape. Normally it runs continuously or something,
>> but those commands allow you to temporarily disable or enable
>> migrations.
Should the blockscanner feature be removed?