Re: Oracle base

Replies embedded ...

On Fri, 17 Dec 2004 14:22:00 -0900, "David E. Grove" <david_grove_at_correct.state.ak.us> wrote:

>
>"Ed Stevens" <nospam_at_noway.nohow> wrote in message
>news:sdd6s0l24om0kcn7s09oqp0kmdm3vql3pt_at_4ax.com...
>> On Fri, 17 Dec 2004 08:26:41 -0900, "David E. Grove"
>> <david_grove_at_correct.state.ak.us> wrote:
>>
>> >I have previously been DBA of Informix on Sun Solaris platform. I am now
>> >familiarizing myself with Oracle.
>> >
>> >Consistency being the hobgoblin of small minds, I have an inclination to
>> >make the Oracle base directory consistent with other stuff.
>Specifically,
>> >I'd like to make it "/opt/oracle".
>> >
>> >Will this bite me in the future?
>> >
>> >Thank you.
>> >
>> >DG
>> >
>> >
>> >
>> >- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
>> >"I think not," said Descartes, and disappeared.
>> >
>>
>> I don't have any links handy, but if you'll poke around on the web you
>> should be able to find a paper by Carey Milsap called 'The OFA
>> Standard - Oracle for Open Systems'. It is almost ten years old now,
>> but I believe it is still the definitive paper on defining your
>> directory structure for Oracle. A somewhat more concise statement of
>> the same principals is located in Appendix G of the "Oracle9i
>> Adminstrator's Reference Release 2 (9.2.0.1.0) for Unix Systems."
>> Available at tahiti.oracle.com.
>>
>> Our implementation looks like this:
>>
>> /u01/app/oracle < this is ORACLE_BASE
>> /u01/app/oracle/product/9.2.0 <-- this is ORACLE_HOME
>> /u01/app/oracle/admin
>> /u01/app/oracle/admin/<sid name>
>> /u01/app/oracle/admin/<sid name>/bdump
>> /u01/app/oracle/admin/<sid name>/cdump
>> /u01/app/oracle/admin/<sid name>/pfile
>> /u01/app/oracle/admin/<sid name>/scripts
>> /u01/app/oracle/admin/<sid name>/trace
>> /u01/app/oracle/admin/<sid name>/udump
>>
>> While Oracle doesn't really care where you put things, as long as you
>> tell it, I'm not enough of a Unix SA to know if there might be some
>> admin gotchas by placing it in the /opt directory. Other than that,
>> the structure still works:
>>
>> <whatever>/oracle < this is ORACLE_BASE
>> <whatever>/oracle/product/9.2.0 <-- this is ORACLE_HOME
>> <whatever>/oracle/admin
>> <whatever>/oracle/admin/<sid name>
>> <whatever>/oracle/admin/<sid name>/bdump
>> <whatever>/oracle/admin/<sid name>/cdump
>> <whatever>/oracle/admin/<sid name>/pfile
>> <whatever>/oracle/admin/<sid name>/scripts
>> <whatever>/oracle/admin/<sid name>/trace
>> <whatever>/oracle/admin/<sid name>/udump
>>
>> Thanks.
>>
>> - Ed Stevens
>>
>> Cohn's Law: The more time you spend in reporting on what you are doing,
>the less time you have to do anything. Stability is achieved when you spend
>all your time doing nothing but reporting on the nothing you are doing.
>
>
>Ed,
>
>Thank you-- you just answered another question I was about to ask.
>
>I wondered why the use of apparently unnecessarily long paths. For
>instance, "$ORACLE_BASE/product/10.1.0/db_1" (from the Install Guide.
>
>I didn't see the purpose for "product". But, I see form your example, that
>there will be another directory ("admin") that will also be at that level in
>the path. So, that now makes sense. The "db_1" didn't make a lot of sense
>either, until I realized that (trying to use terms carefully here to avoid
>confusing Informix and Oracle terminology) a distinct instance, and,
>therefore, a distinct Oracle home directory, is required for each database
>(if one requires multiple databases). That explained the "db_1".
>

No, a distinct oracle_home is NOT required for each database, nor even necessarily recommended. There has been some discussion recently on the pros/cons of creating a distinct logon acount and ORACLE_HOME for each instance, it is not the most commonly used approach, as far as I can tell. (FWIW, I build my servers with a single ORACLE_HOME, but I have a set that I inherited that have separate logon accounts and ORACLE_HOMEs for each database). ORACLE_HOME points to where Oracle itself is installed. The only database specific files there are the password files and possibly the init parm or spfiles, and these are distinguished by includeing the sid name in the file name -- not by creating db specific directories.

>How about the "app", as in "/u01/app/oracle", in the Oracle base directory?
>And the "/u01", which doesn't seem to mean anything in particular, and is
>not used by anything else, as far as I can tell. This is why I want to just
>use "/opt" instead of "/u01/app".
>

The 'app' directory is just a convention we fell into somehow. The reason is lost in the mists of history.

>I now understand from yours and others comments that the Oracle base doesn't
>matter to Oracle (which is what I was concerned about). It sure doesn't
>matter to Solaris (since that is the purpose of "/opt"-- unless you are an
>"old timer" in which case you would use "/usr/local").
>
>Anyway, thank you. I plan to use "/opt/oracle" as Oracle base, and I will
>stick with the Oracle convention of
>"<oracle_base>/product/10.1.0/<database_name>" for Oracle home.

Again, I see no reason to include a /<database_name> directory at that level. Set ORACLE_HOME to $ORACLE_BASE/product/<version> and be done with it.
>
>Lastly, is there any reason (either a real danger or violation of common
>Oracle practice) not to mount a file system at "<oracle_base>/oradata/" to
>use for all the data?

Unless this is an extremely low-load system, you probably don't want to do that. You want to spread your data around to avoid contention and get some multiplexing of critical files. Again referring to the OFA, we get something like:

<mount-point-1>/oradata/<databse_name>/<file_name> <mount-point-2>/oradata/<databse_name>/<file_name> etc.

>
>Thank you, again.
>
>
>Regards,
>
>DG
>
>

Thanks.

• Ed Stevens

Cohn's Law: The more time you spend in reporting on what you are doing, the less time you have to do anything. Stability is achieved when you spend all your time doing nothing but reporting on the nothing you are doing. Received on Mon Dec 20 2004 - 08:38:51 CST