Last week, got this issue reported by a DBA that he wasn’t able to su to oracle user from root on a Oracle Base Database VM in OCI. The login of opc user worked fine and he could do sudo su to root but he couldn’t su to oracle. When he did it just came back to root shell.
[root@xxx ~]# su - oracle
Last login: Fri Jan 12 10:20:38 UTC 2023
There was nothing relevant in /var/log/messages or /var/log/secure. I tried it for some other user and it worked fine. Then I suspected something with the profile of oracle user and voila ! The .bashrc looked like this
[root@xxx oracle]# pwd
[root@xxx oracle]# more .bashrc
So the moment it logged in with user oracle, there was an exit command in .bashrc and it used to exit. Problem solved. I don’t know who did it but it looks like a mischief done by someone.
In part 1, we discussed few things that you should take care before implementation of a ZDLRA. In this post, we will discuss few more things that you should review before or at the time of implementation:
- If you are getting two ZDLRAs (one each for primary and standby sites), there are two ways they can be deployed. One scenario is where all the primary databases (or the database that have no standby) backup to RA at the primary site and then the data is replicated from primary RA to RA at the standby site. This works well for the DBs that have no standby database. For the DBs where there is a standby database, there is a better architecture that can be deployed. In that scenario, primary databases backup to primary RA and the standby databases backup to standby RA. That saves you all the traffic over replication network. Oracle has published a whitepaper on how to do this configuration. Few of the instructions in this paper are a bit dated but it gives a good overall idea of how to do the implementation.
- Keep an eye on the features supported for different DB versions. An interesting one is that real-time redo shipping from standby databases is supported on 12c+ databases only. It is not supported for 11g. There could be other similar things. MOS note 1995866.1 has these details.
- Depending upon the ZDLRA software version being deployed, it may need a minimum version of EM and the ZDLRA plugin. MOS note 2542836.1 has these details.
- Make sure after discovering the the primary and standby databases in EM, their primary-standby relationship is reflected.
- Real-time redo sent to ZDLRA is compressed but the archive logs backup will be compressed only if you use compression in the RMAN command. It is always good to include backup archivelog command with daily incremental job to make sure that no archive log is missed.
- Many of the environments have separate networks for backup traffic. Make sure the backup traffic to ZDLRA uses DB server’s backup network. If that is not the case, you may need to add an explicit route on DB server for ZDLRA client/VIP/scan IPs.
- There are going to be different users that you will need to use: one OS user for deploying the EM agent, one DB user that will be used to run the backups. Depending upon your environment, it may oracle OS user, SYS DB user or could be some other named user created for this purpose.
In next few posts, we will discuss some of the issues I have faced while doing ZDLRA implementation for some customers.
PS: Fernando Simon has written some brilliant posts related to ZDLRA on his blog. I highly recommend to review all of them. Brilliant stuff.
Zero Data Loss Recovery Appliance (ZDLRA) is Oracle’s solution for database backups. It has many advantages over other backup solutions that are available in the market. This post has a brief introduction to ZDLRA and few links for further reading. This is a quick post about few of things that you should keep in mind if you are planning to get a ZDLRA (RA in short). Of course, there is a lot more that is needed while executing the whole plan, but these are some of the basics:
- The very first thing is capacity planning. Depending upon the number & sizes of the DBs that you plan to backup, you need to choose the required configuration. In most cases, an Oracle guy would be doing this for you but you should actively participate in the exercise by providing all the necessary information so that the calculations can be as accurate as possible.
- Another things that plays an important role in deciding the capacity needed is the retention period i.e. period for which you would like to keep the backups in RA. More the number of days, more is the space that you will need.
- Another important thing to consider is whether you are getting only one RA (for primary or standby site) or getting two of them i.e. one each for primary and standby site. Both scenarios need different type of configurations (including the bandwidth requirements between primary and standby sites) so it needs to be planned accordingly.
- One more aspect you need to consider is long term retention. It could be Oracle Cloud object storage or some tape solution.
- Once you have enabled DB backups to ZDLRA, you will need to stop all other backups. Plan that accordingly. Oracle provides way to run the legacy and ZDLRA backups together but that is for short duration i.e. when you are migrating from legacy backups to ZDLRA. That is not really a way to run 2 backup strategies together for long term.
In the next post, will talk about few more things that are important at the time of actual implementation.
It was started by Tim Hall in 2016. This is a Thank you community post. There are so many experts posting on Oracle related forums, doing blog posts, sharing their scripts with everyone. All of you are doing a great job. I would like to mention three names especially:
Tim Hall : Tim is a legend ! I don’t consider something a new feature until Tim writes about it 😀
Jonathan Lewis : I don’t think there is anyone on this planet who has even once worked on a performance problem and hasn’t gained something from the knowledge shared by him on forums or in one of the blog posts.
Tanel Poder : His hacking sessions, blog posts and scripts are awesome. And ashtop is amazing man !
Thank you all of you. We learn from everyone of you. Keep rocking !