[ClusterLabs] convert already clustered LVM to cLVM

[Digimer]

On 28/06/17 04:46 AM, Cristiano Coltro wrote:
> Hi all,
> 
>  
> 
> A brief History
> 
>  
> 
> Customer of mine has setted up a SLES 11 sp3 and SLES11sp4 HA
> environment and he has some LVM as resources.
> 
>  
> 
> When he tries to expand LVM for a “need of space” reason he wasn’t able
> to extend cause a corruption of metadata that even if recovered with
> vgcfgrestore doesn’t heal.
> 
>  
> 
> The customer has not configured LVM with the “c”( clustered ) attribute
> 
>  
> 
>    95   VG        #PV #LV #SN Attr   VSize   VFree
> 
>    96   vg00        1   3   0 wz--n- 279.22g  88.22g
> 
>    97   vgWP4       2  10   0 wz--n-  49.97g   5.97g
> 
>  
> 
> that prevents to extend the LVM and gets
> 
>  
> 
> 83664       Setting global/locking_type to 3
> 
> 83665       global/wait_for_locks not found in config: defaulting to 1
> 
> 83666       Cluster locking selected.
> 
> 83667     connect() failed on local socket: No such file or directory
> 
> 83668     Internal cluster locking initialisation failed.
> 
> 83669       Setting global/fallback_to_local_locking to 1
> 
> 83670       locking/fallback_to_local_locking not found in config:
> defaulting to 1
> 
> 83671     WARNING: Falling back to local file-based locking
> 
>  
> 
>  
> 
> Cause he has the file locking set to 3 ( correctly ) but he must have
> the “c” attribute to work properly.
> 
>  
> 
> Coming to my question:
> 
>  
> 
>   * Is there a way to convert the LVMs without pain to cLVMs?  I know
>     that technically a vgchange -cy do the trick but I’m not sure which
>     impacts it can have.
> 
>  
> 
> Thanks in advance
> 
> Cristiano

So to confirm, they have locking type = 3, but vgdisplay does not show
clustered? I've not tried this myself in ages, but yes, 'vgchange -cy
...' should do the trick. It's possible to have
fallback_to_local_locking = 1 and a mix of clustered and non-clustered
VGs on the same box, so toggling a VG's cluster flag should be pretty
run of the mills.

Test on a dev/test cluster first, to be extra safe.


-- 
Digimer
Papers and Projects: https://alteeve.com/w/
"I am, somehow, less interested in the weight and convolutions of
Einstein’s brain than in the near certainty that people of equal talent
have lived and died in cotton fields and sweatshops." - Stephen Jay Gould