[OpenAFS] How to stop the access to an AFS volume ?

giovanni bracco bracco@frascati.enea.it
Wed, 27 Oct 2004 11:51:01 +0200


On Tuesday 26 October 2004 17:42, Jeffrey Hutzelman wrote:
> On Tuesday, October 26, 2004 10:13:42 -0400 Derrick J Brashear
>
> <shadow@dementia.org> wrote:
> > On Tue, 26 Oct 2004, giovanni bracco wrote:
> >> Is there a way to prevent users to access a selected AFS volume for some
> >> time without affecting the access to the other volumes on the same or on
> >> other file servers & partitions?
> >>
> >> I would like also to be able to stop any current activity on the volume
> >> content.
> >>
> >> In our AFS cell I have observed that there is a small numer of Volumes
> >> that appear as "Off-line" from vos examine or vos listvol command.
> >> Typically these "Off-line" volume have another version which is marked
> >> "On-line" on a different server/partition.
> >> I have the impression that the only way to set a volume "off-line" is
> >> from command vos restore -offline, is that true?
> >> So off-line ha probably nothing to do with what I am looking for.
> >
> > You can use the hidden vos offline command.
>
> You can, but be aware that this status is represented as state in the
> running fileserver, and will be lost if the fileserver restarts.
>

Thank you for the suggestion, I have tried the vos offline command:

vos offline <server_name> <partition_letter> <volume name> <seconds to remain 
offline>

During the offline period the volume is marked by "busy" status
e.g.:

[olavo@bracco bologna]$ vos examine user.bracco_bol
**** Volume 2258391753 is busy ****

so I can NOT make any action on the volume:

vos dump -server f50.bologna.enea.it -partition c -id user.bracco_bol -file 
/tmp/vol_user.bracco_bol

Could not start transaction on the volume 2258391753 to be dumped
VOLSER: volume is busy
Error in vos dump command.
VOLSER: volume is busy

---

It may be is better if I explain the reason for which I would like to put 
"off-line" a volume:

In my AFS cell many volumes have an anomalous Vol ID: it can be seen in the 
previous example: ID=2258391753

The ID is very large and it is larger that the max value that can be managed 
by standard AFS code (signed integer). 
When the problem appeared in the past, Transarc provided us with a patched AFS 
version that is able to manage this kind of vol ID. 
Now I would like to go back to a normal situation, so that I can use OpenAFS 
software on file server.
To attain this I have to convert volumes with anomalous Vol ID into standard 
volumes and I have seen that I can do that by a vos dump and vos restore 
sequence.
I would like to be sure that any user is not able to make any modification to 
a selected volume while the vos dump and vos restore sequence is in progress 
and that is the reason to look for a "off-line" feature.
Alas the vos offline command seems not to be what I was looking for.

Any other suggestions?

GIovanni



-- 
Giovanni Bracco
ENEA INFO 
(Servizio Informatica e Reti)
Via E. Fermi 45
I-00044 Frascati (Roma) Italy
phone 00-39-06-9400-5597
FAX   00-39-06-9400-5735
E-mail  bracco@frascati.enea.it
WWW http://fusfis.frascati.enea.it/~bracco