Oracle Rant

I wrote previously about integrating RMAN with Veritas NetBackup. The reason for doing so was so that I could easily verify that the backup went to tape and for recovery to be simpler. By integrating, I no longer needed to contact my NetBackup admin should I quickly need to recover my database. Also, as long as NetBackup was installed on multiple servers, I could easily clone/duplicate/restore my databases on any number of servers where it was installed. I am also using a recovery catalog to help simplify things. Without a recovery catalog, you will need to restore your control file which will have information about your backups, spfile, and previous control file backups prior to being backed up itself.

A couple of things to note. I only have 1 NetBackup policy of Oracle type assigned to this server by my Veritas NetBackup admin. Also, that policy is set to infinite retention so that RMAN controls when it wants to delete expired / obsolete backups by allocating a channel "for maintenance device type ‘SBT_TAPE’. A good practice is working with your NetBackup admin in order to configure your policy. You could also define multiple policies so he can more easily identify which backups to send offsite. The only problem with this approach, and it’s very minor at that, is that you will have to explicitly define your Oracle type NetBackup Policy when you do your backups. Read the rest of this entry »

Backup and Recovery is one of the most critical tasks that a DBA has to perform. Sadly, it is also one of the most misunderstood. RMAN should be the tool of choice for backup and recovery for Oracle databases. There is so much that can be done with RMAN. What Robert and Matthew do is break it down piece by piece. There is a great intro and they build on that in subsequent chapters. If you want to link RMAN directly with your backup software (i.e. Veritas, EMC, Legato, etc..) then the authors show you how. I used the Veritas piece to link RMAN in and it worked flawlessly. They go over the latest features including block changing files (for faster incremental backups), merging level 1 and level 0 backups (for faster recoveries without the overhead of backing up the whole database), and even cover what the flash recovery area is and how to use it. There is so much great material packed in this book. Yeah, you can try and read Oracle’s docs, but rather than just show you how to do it, the authors also teach you why to do it. You can read this book chronologically or use it as a reference. The authors writing style make this book a great joy to read. They also include a lot of great examples in case you like to learn by seeing. I would highly recommend this book if you are an Oracle DBA, whether you use RMAN or not. Afterall, RMAN is what you should be using .

I just recently got RMAN working with NetBackup. I have been asked to document this at work . Coincidently it makes for a great blog post!

#1. It is very important that you document things and how they are done so that other people can learn how to do them, know how it is done, and you can have a standard based off of this. It also gives you a baseline to improve upon. If you don’t believe me, read the book “The Goal”.

First, let me explain why we used RMAN and then why we linked it with Veritas. RMAN gives you so much flexibility and control of your backups. It might seem mundane at first, but once you get into the thick of it, you realize how powerful it is. There is an interface to RMAN through database control / grid control but I think Oracle still could improve greatly upon it. They leave many options out, but if the goal is simplicity and to get someone to do it, it is very powerful in that regard. I guess something is better than nothing, but really it’s pretty good but could be much better. How’s that?

RMAN also checks for corrupted blocks and can assist you with recovering them. It can keep track of block changes through a tracking file. This way it does not have to scan every block to see if it has changed. Even more powerful, if you have not compressed your backups, you can merge your level 1 and your level 0 to create a new level 0 backup. This can greatly speed up recovery times. I could go on and on but RMAN is a very powerful utility. I will blog more about it later.

Second, why did we want to link it with Veritas Netbackup? Well Veritas Netbackup is the corporate standard. You could just as well link it with EMC Networker and Tivoli Storage manager and any other backup vendor that makes a library to link RMAN with the MML. Before, we would have to have the backup person pull our Oracle backups off disk or we would execute a script after they went to disk. The problem is when the system crashes and we have to wake our backup person in the middle of the night to restore our files. If we find out it is the wrong one, we wake him up again. Recoveries take longer and the company loses money. By integrating RMAN with the Veritas Backup Agent we can now restore without having to wakeup our Backup Admin. Why? Because RMAN talks directly with Veritas when it backs up so that it is able to tell Veritas what it needs when it is time to recover.

Read the rest of this entry »