Re: Mirrored disks Vs duplexed logs

Richard Flores <flores_at_ccnet.com> writes:

>What would you do where you were not multiplexing from within
>Oracle and inadvertently deleted one of the online redo log files?

Update my resume? What if you delete one of the tablespace data files? What if you accidentally type "init 1" instead of "init q"? What if....

>OS mirroring would happily delete the file wherever it might exist.

What's the point? If you give someone a loaded gun (the root or oracle account password) and they don't know how to safely handle that responsibility....

System administration priveleges come with a certain amount of responsibility to act with professionalism and due diligence in ones actions.

Having said all that I generally do recommend to my customers that they use log groups with two members. This is less performant than OS level mirroring, but worth the extra safety. The problem with OS level mirroring in this case is that it does not understand the contents of the redo logs and cannot be counted upon to choose the proper plex as the master for a resilvering operation. This doesn't matter with the data files, but can be important with respect to the active redo log.

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