[Starcluster] WebFeedback - cluster: Is it possible to create EBS volume based on snapshot ... [help.mit.edu #1114722]

[Justin Riley]

Hi Gen-tao,

I get what you're saying now and for the current stable version of StarCluster 
the short answer is: No. However, I'm currently working on the next version of 
StarCluster and I will provide a way at the command line for creating new EBS 
volumes (same as ElasticFox does). I hadn't thought about creating EBS volumes 
from snapshots but this is of course a good idea that I will likely use in the 
next version of StarCluster.

Using a flag in the config (ie SNAPSHOTID="xxxx") though is not the best 
solution for this because then I would have no way of knowing whether a EBS 
volume had been created in the past for that SNAPSHOTID or not. And even if I 
could, how would I know which volume you meant to use since multiple ebs 
volume could have been created from that snapshot id? Or does the flag mean 
always create a new volume (which i can't see the benefit of and costs money)? 
There's far too much ambiguity and in any event wouldn't be straight forward 
for the user.

A better way to do this would be to have you explicitly tell starcluster at 
the command line that you want to create a new volume (from snapshot id):

ie.

$ starcluster createvolume --snapshotid xxxx --size 10
$ ....
$ ...
$ Your new EBS volume ID is: xxxxxxx
 

Then you would explicitly specify the new volume id in the config the way it 
is now. This is likely how I will implement this in the next version.

This is how you will be able to create EBS volumes in the next version. 
However, this can be done manually with the current stable version of 
StarCluster. Simply use ElasticFox to create a new EBS volume from a snapshot 
(as i described in the previous email) and then use the new EBS volume id in 
your StarCluster config. Does that make sense?

I will announce the next version on the starcluster mailing list (cc'd on this 
email):

http://mailman.mit.edu/mailman/listinfo/starcluster

BTW, you have joined the mailing list right?

Hope this helps,

~Justin

On Thursday 07 January 2010 4:29:48 am Gen-Tao Chiang wrote:
> Dear Justin
> 
>    Thank you fro your email! What I mean is:
> Creating "NEW" EBS volume using a EBS snapshot. For example, in
> .starcluster configuration file
> using a flag like this SNAPSHOTID="xxxx" so a new EBS volume will be
> created based on this snapshot and attach to either master or work nodes
> directly.
> 
> Best Regard!
>             Gen-tao
> 
> Justin Riley wrote:
> > Hi Gen-Tao,
> >
> > I need a little clarification. Do you mean is it possible to use an EBS
> > snapshot with StarCluster? If so, it should work. That being said, I
> > haven't tested it so your mileage may vary. If you try it I would greatly
> > appreciate your feedback on whether or not it worked and what your issues
> > were.
> >
> > If you're asking about creating a *NEW* EBS volume from an EBS snapshot
> > then yes this can be done using the ElasticFox
> > (https://addons.mozilla.org/en- US/firefox/addon/11626) plugin for
> > Firefox. In the "Volumes and Snapshots" tab, simply right click a
> > snapshot and choose "Create New Volume from this Snapshot".
> >
> > Hope that helps,
> >
> > ~Justin
>