tech-kern: Re: Which snapshot strategy to use? was: How to capture all file system writes

Subject: Re: Which snapshot strategy to use? was: How to capture all file system writes
To: Christian Limpach <chris@pin.lu>
From: Jason Thorpe <thorpej@wasabisystems.com>
List: tech-kern
Date: 10/22/2003 18:10:41

On Wednesday, October 22, 2003, at 11:17  AM, Christian Limpach wrote:

>> 2) A somewhat generic approach similar to the fssnap from Solaris:
>>    - The snapshots get cleared on unmount.
>
> why?  I have an implementation of this that can write the map to the
> snapshot backing device...
>
> FWIW I use a pseudo disk device to do block interception.

What is the procedure you use for snapshotting a file system?

Let's say you have /u1 mounted from /dev/sd1a.  How would you then take 
a snapshot?

         -- Jason R. Thorpe <thorpej@wasabisystems.com>