Re: RawDevice??

Steve Miller wrote:
>
> You can also use symlinks (which is how we do it).
> (I'm not that familiar with Solaris, so please substitute the appropriate
> disk locations/terms)
>
> First, create your logical (virtual) disk for your datafile. Then, from
> the dbs directory, issue the following command:
>
> ln -s /dev/rdsk/datafile_name datafile_name
>
> In your create database/create datafile command, give the absolute path to
> the link, not the raw device. Additionally, when you specify the size of
> the datafile, ensure you subtract at least 2 data blocks for Oracle
> overhead. When the datafile is created, it will be created on raw devices,
> but you'll be able to use the link to address the file. This not only
> eases the ability to create raw disk datafiles, but also gives you the
> flexibility of going back to a filesystem if you choose to. As long as the
> specific datafile is not too large to be a "file" in a filesystem (the old
> 2 GB limit on some systems) you can back up the datafile (using dd) off to
> tape, remove the link, and then restore the datafile to the dbs directory.
> The control files will still remember the datafile exists in the dbs
> directory (where the link use to reside) and you'll be able to re-start the
> instance and open the database with no additional work required.
>
>
>

This is not true. In many of the Unix systems image of a raw device will not correspond to that of the standard file. You have to skip the raw device header before you make a standard file out of it. Received on Tue Aug 26 1997 - 00:00:00 CDT