gconcat

[Eric Anderson]

Lapo Nustrini wrote:

> On Dec 16, 2005, at 8:32 AM, Pawel Jakub Dawidek wrote:
>
>> On Fri, Dec 16, 2005 at 08:10:51AM -0800, Lapo Nustrini wrote:
>> +>
>> +> On Dec 15, 2005, at 6:17 PM, Pawel Jakub Dawidek wrote:
>> +>
>> +> >On Thu, Dec 15, 2005 at 04:06:08PM -0800, Lapo Nustrini wrote:
>> +> >+>
>> +> >+> Can anyone tell me whether it is possible to expand a  gconcat 
>> volume (by adding a drive to the end of it) without having  to wipe 
>> the data from the existing set and recreate from scratch?
>> +> >+> I don't mind having to manually edit bsdlabels and such.   
>> Just wondering if its possible at all.
>> +> >+> I've been looking for some docs on this but can't seem to  
>> find a definitive answer.
>> +> >
>> +> >It should just work be relabeling providers.
>> +> >If you did something like:
>> +> >
>> +> >    # gconcat label foo da0 da1
>> +> >
>> +> >You can expand it with:
>> +> >
>> +> >    # gconcat label foo da0 da1 da2 da3
>> +> >
>> +> >etc. Just be sure the order of old providers is the same.
>> +> >
>> +> >PS. You'd need to stop device 'foo' first.
>> +> >
>> +>
>> +> This is what I tried:
>> +>
>> +>     # mount /dev/concat/gc0 /mnt
>> +>     # cp -pr ttt /mnt
>> +>     # ls -la /mnt
>> +>     total 8
>> +>     drwxr-xr-x   4 root  wheel      512 Dec 16 07:49 .
>> +>     drwxr-xr-x  25 root  wheel     1024 Dec 15 15:02 ..
>> +>     drwxrwxr-x   2 root  operator   512 Dec 16 07:48 .snap
>> +>     drwxr-xr-x   2 lapo  wheel      512 Nov  9 22:48 ttt
>> +>     # umount /mnt
>> +>     # gconcat stop gc0
>> +>     # gconcat label gc0 ad1 ad3 ad4 ad6 ad7
>> +>     # mount /dev/concat/gc0 /mnt
>> +>     # ls -la /mnt
>> +>     ls: ttt: Bad file descriptor
>> +>     total 6
>> +>     drwxr-xr-x   4 root  wheel      512 Dec 16 07:49 .
>> +>     drwxr-xr-x  25 root  wheel     1024 Dec 15 15:02 ..
>> +>     drwxrwxr-x   2 root  operator   512 Dec 16 07:48 .snap
>> +>
>> +> Am I missing a step?
>> +> Thanks!
>>
>> Are you sure you gave correct order? It works here just fine...
>> What was the previous 'gconcat label' command you gave?
>>
>
> I was thought the previous command was,    "#gconcat label gc0 ad1 ad3 
> ad4"
> However, to make sure I tried this again and it does indeed appear to  
> work.
> I do have a further question.
> If I create a new volume with:
>     #gconcat label gc0 ad1 ad3
> Then place a file system on it:
>     #newfs -U /dev/concat/gc0
> And mount it, the output from "df" will be:
>     /dev/concat/gc0     15135708       4 13924848     0%    /mnt
>
> If I then umount and stop the gconcat  volume, add aother drive to it  
> with:
>     #gconcat label gc0 ad1 ad3 ad5
> I can't run newfs on it or I will lose any data, but the output of  
> "df" will still only show:
>     /dev/concat/gc0     15135708       4 13924848     0%    /mnt
>
> Is there a way to tell the system the drive is now bigger?  Should I  
> be using bsdlabel / fdisk at some point?


You can use growfs to do that.

Eric


-- 
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Eric Anderson        Sr. Systems Administrator        Centaur Technology
Anything that works is better than anything that doesn't.
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