Re: RMAN Confusion

From: Andrew Kerber <andrew.kerber_at_gmail.com>
Date: Wed, 3 Jun 2015 07:14:54 -0500
Message-Id: <07108218-44E7-490D-9451-1213C2D60B3B_at_gmail.com>



Great advice. If classes are not an option, books and lots of practice is the best you can do.

Sent from my iPad

> On Jun 3, 2015, at 5:50 AM, Stefan Knecht <knecht.stefan_at_gmail.com> wrote:
> 
> What I would do is get a VM ( or Oracle  Virtualbox, which is free) up and running with an Oracle database on it, and toy around with it. Once it's up and running, create a snapshot so you can just revert if you mess it up, or rather when you mess it up because you most certainly will :) (which is kind of the point of the whole thing and it's how you learn the most). If your workstation / laptop has a couple GB of RAM it'll run. It won't perform stellar, but it doesn't need to. It will serve just fine to toy around with backup and recovery. 
> 
> Having solid fundamentals on the subject is key to being able to even begin to think about a BR strategy. The best way to learn is by just doing it. But doing it somewhere where no harm can be done. I'm sure if during your testing you hit a specific error or problem that the list will be glad to help. I'd build a list of various scenarios to play through, such as "what if I loose my controlfiles?" "What if I loose one datafile?" "What if I have corrupt data blocks?" etc etc..
> 
> Plus, if you really want to rely on USB media to store your backup, what you want to look into sooner rather than later is the RMAN validate functionality, and  you want to test your backups / restores more often than not. But if the data in this database is of any importance, investing a little bit of money in proper storage (it doesn't need to be huge from the sound of it) would seem the better strategy.
> 
> Regarding the pictures - if they're on the OS, you can't back them up with RMAN. Only data that's actually stored within the database can be backed up with RMAN - so the pictures would have to be stored as BLOB or intermedia (or Multimedia as it's called in newer versions ) data types. If you're stuck with them on the filesystem you need to back them up using the same software you're backing up your OS with. But in doing that you'll loose the transactional link between your data inside the database and the pictures. If you want to retain that link, the only way to do so reliably is by storing the pictures in the database itself.
> 
> Stefan
> 
> 
> 
> 
> 

>> On Wed, Jun 3, 2015 at 10:23 AM, Ed Hoeffner <hoeff001_at_umn.edu> wrote:
>> Hi
>>
>>
>>
>> Thank you all for the info. While a class would be preferred, that is, unfortunately, not in the cards. However, having a recommended author is invaluable and is the way I’m going to have to go. As Ronan said, it is my butt (and more) on the line but there are limitations to what I can do.
>>
>>
>>
>> The responses received were about what I expected as I knew this isn’t simple. I would argue this is more like “I have a really great car. How do I fix it?” Hopefully, Darl Kuhn is the Chilton of the RMAN world.
>>
>>
>>
>> As for the USB warning, all I can say is thanks Seth. I’m fairly sure I wouldn’t get info like that anywhere else. I’m not sure how I’m going to deal with that, but forewarned is forearmed.
>>
>>
>>
>> Anyway, thanks for the help. I’ve some more reading to do…
>>
>>
>>
>> Ed
>>
>>
>>
>> From: Seth Miller [mailto:sethmiller.sm_at_gmail.com]
>> Sent: Tuesday, June 02, 2015 2:30 PM
>> To: Ronan Merrick
>> Cc: MARK BRINSMEAD; hoeff001_at_umn.edu; oracle-l; Andrew Kerber
>> Subject: Re: RMAN Confusion
>>
>>
>>
>> Ed,
>>
>>
>>
>> Just as a word of caution, using USB drives on Windows as your RMAN backup destination is very risky. Although, I'm sure others have figured it out, every customer I have worked with that was using USB drives as their RMAN backup destination in Windows has had corrupt backups, either sporadically or entirely.
>>
>>
>>
>> Seth Miller
>>
>>
>>
>> On Tue, Jun 2, 2015 at 2:48 AM, Ronan Merrick <merrickronan1_at_gmail.com> wrote:
>>
>> Hi Ed,
>>
>> As Mark and Andrew have said you really should think about getting some help or training if possible. If anything happens it will be your ass on the line. You may succeed in getting the backups up and running but recovering the database is a whole other story. Darl Kuhns RMAN recipe book helped me a lot at the start.
>>
>> Ronan
>>
>> On 2 Jun 2015 05:47, "MARK BRINSMEAD" <mark.brinsmead_at_gmail.com> wrote:
>>
>> This sounds like pretty good advice, Andrew. The OP might also want to think about hiring a consultant -- maybe a business consultant -- to help work out both the goals of a business continuance plan and the implementation of one.
>>
>> So far, the original question sounds a lot like "I would like to build my own automobile. I have been told that steel is a good material, but I don't know much about it and I don't yet know where to obtain any. Can you help..."
>>
>> The fact of the matter here is that I can help in this case, as -- most likely -- can most of the other people frequenting this list. But the question is far too broad and the subject far too complex to even attempt to address by e-mail. Of course, even if I could, I probably wouldn't, since answering questions like this is how I normally earn my living. :-)
>>
>>
>> Ed, you might find it helpful to look over the backup and recovery "concepts" manual. After you have read this, you will probably have most of the knowledge that the reference manual assumes you to have. Taking a 3 day course is probably a good idea, though, anyway.
>>
>>
>>
>> On Mon, Jun 1, 2015 at 11:03 PM, Andrew Kerber <andrew.kerber_at_gmail.com> wrote:
>>
>> In your case, my best advice is to take one of the 3 day oracle backup and recovery courses. You will really need a better understanding than we can give just by answering your questions here. Once you take the course, build your own instances and experiment.
>>
>> Sent from my iPad
>>
>>
>> On Jun 1, 2015, at 9:36 PM, Ed Hoeffner <hoeff001_at_umn.edu> wrote:
>>
>> Hi
>>
>>
>>
>> I’m trying to develop DR plans for an application we run that’s built on top of Oracle. According to what I’ve read, RMAN is the recommendation. After going through the RMAN docs a couple of times, I still feel I don’t know enough to actually make a plan to depend on, so I’m hoping someone can put me on the right path without too much bother.
>>
>>
>>
>> The app is not very busy by any standards that might come up here. It supports a liquid handling system that mixes a bunch of solutions together and then periodically over the next month or so takes pictures. The DB is used to keep track of all that from entry to exit from the system. The pictures are stored as a filename, so the picture files themselves also have to be backed up. At the moment, the plan is run RMAN incrementals daily from the AT queue to a USB disk. The picture files should be discoverable through some SQL, though I can envision a way to find them with a shell script (ugh!).
>>
>>
>>
>> I think I want to use a catalog because the changes are kept in the recovery area. I’m confused between archive-redo logs, control files, the catalog, snapshot files, the RMAN copy command, and what constitutes all the info necessary for the backup to be able to be restored. The manual feels like it assumes I know way more than I do, so I don’t feel I know enough to make the decisions here. Would someone please let me know what is really necessary? Is a catalog really the best way to go?
>>
>>
>>
>> The manual talks about RMAN not being able to work across platforms, but I can’t seem to find the definition of a platform. Since this is on Server 2003, it’s going to be wiped and reloaded (probably 2008 – 32 bit), so I’m hoping I can use this to restore the data once that happens. Will that work?
>>
>>
>>
>> In trying to make the initial backup in preparation for turning the archive log on, the shutdown immediate command (wouldn’t transactional be better?) works great, but startup mount (as told in the manual) fails with error ORA-12505 TNS: Listener could not resolve SID given in connect descriptor, so it takes a reboot to get everything back in line. Somewhere in the myriad readings I ran into this, but I can no longer find the answer. How do I bring it up correctly without having to reboot?
>>
>>
>>
>> Is there any way to create something to test with? I only have one shot at this and would really like to get some experience under my belt before I need it.
>>
>>
>>
>> Many thanks!!!
>>
>>
>>
>> Ed Hoeffner
>>

>
--
http://www.freelists.org/webpage/oracle-l
Received on Wed Jun 03 2015 - 14:14:54 CEST

Original text of this message