This article explains how to connect to an Oracle Autonomous database using SQL developer, SQL plus or other tools. When we create an Oracle ADB on OCI, we just can't connect directly to the database even though the Network ACL is disabled. The reason is mTLS authentication is set to Required by default.  Let us see how to connect to the ADB using SQL developer first and then SQL plus. If you have downloaded SQL developer for connecting to your database on cloud, it's super easy to connect. Method 1: Using mTLS   Mutual TLS (mTLS) is a 2-way handshake between a client and ..read more

 I was converting my Oracle ASM disk management from udev rules to ASM Filter Driver (ASMFD) and encountered the below errors which might happen during the conversion operation and this post might help you fix the issue as quickly as possible.  You can read more on Oracle ASMFD, configuration and migrating to ASMFD using this 19c documentation 1. Wrong/incorrect afd_diskstring value [root@ol819-rac1 ~]# [root@ol819-rac1 ~]# $ORACLE_HOME/bin/asmcmd afd_label asmdisk1 /dev/sdb1 --migrate No devices to be labeled. ASMCMD-9513: ASM disk label set operation failed. Since my disks are ..read more

 In my previous post, I explain on how to upgrade Oracle Enterprise Manager (OEM) from 13.4 to 13.5. In my lab environment, I have not installed any additional plug-ins. But this not the case when we did the same in live production environment. We had one plug-in which required to be migrated instead of upgraded as below.  This is clearly indicated when we use GUI to perform the upgrade. If you are using command line to upgrade the OEM, then these prechecks are written to a file which gets buried in the huge number of lines as we tend to check only for any errors or warnings. This ..read more

 In my previous post, we went through the steps of how to upgrade from OEM 13.4 to 13.5. This is the continuation of the post with all the post upgrade steps. Let's dive into action..  Note: If pictures look blurry in the post, please click on them to see the clear picture. Post Upgrade:  Modify the .bashrc or .profile file to reflect the new upgraded OMS home. We did an out of place upgrade and hence the path will be changing. Reflect the changes in the profile file to make our life easier.  OMS will be brought up after the upgrade automatically once upgrade is done.  ..read more

 In my previous post, we went through the steps of patching the Oracle Enterprise Manager (OEM) 13.4 from a lower patch level to a higher patch level 13.4.0.20. If you would like to stay in OEM 13.4, there is no more patches for the same. If you would like to upgrade to the terminal release of OEM 13c, let's check how that can be achieved.  OEM 13.4 to 13.5 upgrade paths There are 2 different path by which the OEM can be upgraded 1. Upgrade End to End Takes long time  Takes to base version and another downtime required to apply RU on 13.5 Needs OEM 13.4 to be version 13.4.0.10 ..read more

 In this blog post, I'll be sharing the steps on how to patch Oracle Management Server (OMS) of the Oracle Enterprise Manager.  Few Tips:  Error correction patching support for OEM 13.4 has already passed and is only available for teminal release of OEM 13c (13.5)  Latest available Release update for OEM 13.4 is RU 20 (released May 2023) Extended support for OEM 13.5 is available until Dec 2026 Next Major release for OEM is planned to launch on 2nd half of 2024.  With the above points in mind, we will look into patching the OEM version 13.4.0.0 of my lab environmen ..read more

 I was trying to patch my lab environment Oracle Enterprise Manager (OEM) OMS to the latest version. While doing so, we have to update the OMSPatcher and OPatch utility both to the latest version available.  After the update to both OMSPatcher and OPatch has been done, I tried running the analyze command where I got a weird error thrown at me as below.  [oracle@linux-8 35174911]$ omspatcher apply -analyze java.lang.NoClassDefFoundError: oracle/oplan/sdk/intg/OPlanIntgFactory at oracle.opatchauto.oms.OMSPatchingSession.<clinit>(OMSPatchingSession.java:75) a ..read more

HugePages is a feature integrated into the Linux kernel. A page is the basic unit of virtual memory, with the default page size being 4096 Bytes in the x86 architecture. Linux uses a mechanism in the CPU architecture called "Translation Lookaside Buffers" (TLB) to manage the mapping of virtual memory pages to actual physical memory addresses. So, when each time memory is accessed using the default page size, there is additional overhead as many TLB resources are consumed. With the implementation of Huge Pages, we are grouping these small pages into a bigger chunk with consuming a sing ..read more

Query optimization or tuning is an interesting subject. Sometimes we would get complaints from application folks that their query is running slow in the timelines of running 4 hours against 1 or 2 hrs normal execution. During these times, we can't wait for the query to run to its completion only to see the query didn't run as expected.  How can we find whether the query is running as expected? One of the simple ways is to run the explain plan to see whether the plan has changed from the existing one and is the join methods and filters are applied as expected and also whether the cost of t ..read more

 Many times, as a DBA we would be required to create database restore points so that if something messed up in the database be it due to a database upgrade or patching, application upgrade touching the database objects, etc., it would be easy to go back to the time when the operation was started without the need of restoring the database.  To facilitate this easy feature, one would need to enable or create the restore point be it a normal restore point or a guaranteed restore point. I will always prefer the guaranteed restore point if I want to secure the database of unexpected mess ..read more