[sheepdog] [PATCH 1/2] collie: add command 'collie vdi rollback'

[MORITA Kazutaka]

At Fri, 31 Aug 2012 13:53:29 +0800,
levin li wrote:
> 
> On 08/31/2012 12:17 PM, MORITA Kazutaka wrote:
> > At Thu, 30 Aug 2012 13:59:54 +0800,
> > levin li wrote:
> >>
> >> From: levin li <xingke.lwp at taobao.com>
> >>
> >> With this command we can rollback a cloned VDI to any specified
> >> snapshot, or easily reset to its parent VDI, the usage is easy.
> >>
> >> To rollback to a specified snapshot:
> >>
> >> $ collie vdi rollback -s 1 base_vdi clone_vdi
> > 
> > Do we need to go back to a snapshot of another vdi?
> > 
> > What I thought was like follows:
> > 
> >   $ collie vdi rollback -h
> >   Usage: collie vdi check [-s snapshot] <vdiname>
> > 
> >   $ collie vdi create test 4G
> >   $ collie vdi snapshot test -s snap1
> >   $ collie vdi snapshot test -s snap2
> >   $ collie vdi tree test
> >   test---[2012-08-31 13:05]---[2012-08-31 13:06]---(you are here)
> >   $ collie vdi list test
> >     Name        Id    Size    Used  Shared    Creation time   VDI id  Copies  Tag
> >   s test         1  4.0 GB  0.0 MB  0.0 MB 2012-08-31 13:05   7c2b25     1         snap1
> >   s test         2  4.0 GB  0.0 MB  0.0 MB 2012-08-31 13:06   7c2b26     1         snap2
> >     test         3  4.0 GB  0.0 MB  0.0 MB 2012-08-31 13:07   7c2b27     1              
> > 
> >   $ collie vdi rollback test -s snap1
> >   $ collie vdi tree test
> >   test---[2012-08-31 13:05]-+-[2012-08-31 13:06]---[2012-08-31 13:07]
> >                             `-(you are here)
> >   $ collie vdi list test
> >     Name        Id    Size    Used  Shared    Creation time   VDI id  Copies  Tag
> >   s test         1  4.0 GB  0.0 MB  0.0 MB 2012-08-31 13:05   7c2b25     1         snap1
> >   s test         2  4.0 GB  0.0 MB  0.0 MB 2012-08-31 13:06   7c2b26     1         snap2
> >   s test         3  4.0 GB  0.0 MB  0.0 MB 2012-08-31 13:07   7c2b27     1              
> >     test         4  4.0 GB  4.0 MB  0.0 MB 2012-08-31 13:08   7c2b28     1              
> > 
> > 
> > Thanks,
> > 
> > Kazutaka
> > 
> 
> Maybe I misunderstood you, but this patch can do more than you expected,
> it's no harm for users to rollback a VDI to any snapshot if they choose to.

I've tried, but it doesn't work well.

$ collie vdi create test 4G
$ collie vdi snapshot test -s snap1
$ collie vdi snapshot test -s snap2
$ collie vdi rollback test -s snap1  <- Can you support this usage?
Segmentation fault                   <- Please fix this
$ collie vdi rollback test test -s snap1
Can not rollback a non-cloned VDI    <- We want to a rollback command even if
                                        the vdi is not a cloned one

Thanks,

Kazutaka