Re: [Mysqlfs-general] Maintaining previous versions.

[Stef B. <st...@bo...>]

Michal Ludvig wrote:
> Binlog was designed for a totally different purpose and as such is 
> hardly usable for a convenient revision tracking on mysqlfs.
>
> For instance you'll have to keep all binlogs from when the FS was 
> created to be able to "replay" the filesystem to some point in time (and 
> honestly who keeps binlogs longer then a few days after they get their 
> way to slaves).
>   
Well, I did not know this way there are backups already available in the 
MySQL server.

I've just read the MySQL reference on the Internet, and it is possible 
to do binary logging
for at least the mysqlfs database.
> It would work on the whole-filesystem level, not for particular files 
> (which may or may not be what Stef wanted).
>   

Yes, indeed. With mysqlbinlog it's possible to go back to a previous 
version of a database, and copy that one to
a temporary database.  But this is step one. The next step would be to 
find the particular file (for a given time).

Ok, it's possible this way, but very complicated if you would like to 
check only one file.

But when reacting on your first remark. In my idea I woul like to use 
the mysql filesystem as a backup, not as
a filesystem where users have direct access to. I do understand that 
when users (or processes) have direct access, there will a lot of 
changes, which all get maintained...

My idea is to only do a copy or a sync of a directory of my choice, for 
example my homedirectory, once a day (4.30 at night for example), to the 
mounted mysqlfs.
This way not every change will get his way to the database.

Of course there should be a policy on how long a version will stay in 
the database, and there should be some utilities to find previous 
versions. But that's not the most difficult step I think.

Stef Bon