Oracle, Linux, AWS, Azure, GCP
May 30, 2025 Leave a comment
While installing Oracle Enterprise Manager 24ai, the check for the parameter value _allow_insert_with_update_check failed:
If the repository database is a PDB, you need to set this parameter at PDB level.
1) Connect to the repository database using sqlplus as SYS user and run:
SQL> alter system set "_allow_insert_with_update_check"=true;
2) Rerun the check:
It succeeded this time:
May 30, 2025 Leave a comment
While installing Oracle Enterprise Manager 24ai, the check “Ensure that the Oracle partitioning option is installed” failed.
Check if the EM repository database (the database you selected for the EM repository) has partitioning enabled:
SQL> select value from v$option where parameter = 'Partitioning';
VALUE
----------------------------------------------------------------
FALSE
The output above indicates that the partitioning is disabled.
Let’s not think about the licensing part yet, since we are currently using Oracle for learning.
If partitioning is disabled, enable it on the database as follows:
1. Shut down the database using srvctl or sqlplus:
srvctl stop database -d orclasm
2. Connect to the database server as RBDMS owner and run the following commands:
$ su - oracle
$ cd $ORACLE_HOME/bin
$ chopt enable partitioning
The output of the command would appear as follows:
Writing to /u01/app/oracle/product/23ai/dbhome_1/install/enable_partitioning_2025-05-30_21-46-30PM.log...
/usr/bin/make -f /u01/app/oracle/product/23ai/dbhome_1/rdbms/lib/ins_rdbms.mk part_on ORACLE_HOME=/u01/app/oracle/product/23ai/dbhome_1
/usr/bin/make -f /u01/app/oracle/product/23ai/dbhome_1/rdbms/lib/ins_rdbms.mk ioracle ORACLE_HOME=/u01/app/oracle/product/23ai/dbhome_1
3. Start the database using srvctl or sqlplus:
srvctl start database -d orclasm
4. Connect to the database using sqlplus and verify the option status again:
SQL> select value from v$option where parameter = 'Partitioning';
VALUE
----------------------------------------------------------------
TRUE
5. Rerun the check again
It shows succeeded this time:
May 16, 2025 Leave a comment
While running asmca, I have got the following error:
Cause - Following nodes does not have required file ownership/permissions: Node :mk23ai-b PRVG-11960 : Set user ID bit is not set for file "/u01/app/oracle/product/23ai/dbhome_1/bin/oradism" on node "mk23ai-b". Action - Run the Oracle home root script as the "root" user to fix the permissions.
Check the current permissions on the file:
oracle@mk23ai-b:~$ ll /u01/app/oracle/product/23ai/dbhome_1/bin/oradism
-rwxr-x---. 1 root oinstall 1138016 Jul 11 2024 /u01/app/oracle/product/23ai/dbhome_1/bin/oradism
The error message includes an action section that states the steps to follow. Connect to the database server as the root user and execute the root.sh script from the RDBMS home directory, since oradism mentioned in the error is located there.
root@mk23ai-b:~# /u01/app/oracle/product/23ai/dbhome_1/root.sh
Performing root user operation.
The following environment variables are set as:
ORACLE_OWNER= oracle
ORACLE_HOME= /u01/app/oracle/product/23ai/dbhome_1
Enter the full pathname of the local bin directory: [/usr/local/bin]:
The contents of "dbhome" have not changed. No need to overwrite.
The contents of "oraenv" have not changed. No need to overwrite.
The contents of "coraenv" have not changed. No need to overwrite.
Entries will be added to the /etc/oratab file as needed by
Database Configuration Assistant when a database is created
Finished running generic part of root script.
Now product-specific root actions will be performed.
Check the file permissions again:
oracle@mk23ai-b:~$ ll /u01/app/oracle/product/23ai/dbhome_1/bin/oradism
-rwsr-x---. 1 root oinstall 1138016 Jul 11 2024 /u01/app/oracle/product/23ai/dbhome_1/bin/oradism
This time it has user ID bit is set.
Normally, when you run a program (an executable file), it runs with your own permissions – meaning it can only do what your user account is allowed to do. But if the setuid bit is set on a file, the program runs with the permissions of the file’s owner, regardless of who is running it.
You can continue using ASMCA this time.
May 16, 2025 Leave a comment
While running the root.sh script, I encountered the following error:
root@mk23ai-b:~# /u01/app/23ai/grid/root.sh
Performing root user operation.
...
/u01/app/oracle/crsdata/mk23ai-b/crsconfig/roothas_2025-05-16_07-10-12PM.log
2025/05/16 19:10:17 CLSRSC-400: A system reboot is required to continue installing.
Died at /u01/app/23ai/grid/crs/install/oraafd.pm line 688.
If you think rebooting the system and rerunning the root.sh script will help, well, no… I’ve already tried :).
Check if the secure boot is enabled:
root@mk23ai-b:~# mokutil --sb-state
SecureBoot enabled
Based on the previous output, Secure Boot is enabled. If you received a different output, such as “Secure Boot disabled,” continue your search.
Connect to the VM and rerun root.sh script:
root@mk23ai-b:~# /u01/app/23ai/grid/root.sh
...
mk23ai-b 2025/05/16 19:32:48 /u01/app/oracle/crsdata/mk23ai-b/olr/backup_20250516_193248.olr 0
2025/05/16 19:32:50 CLSRSC-327: Successfully configured Oracle Restart for a standalone server
May 1, 2025 Leave a comment
Note: The post may seem related to Linux only. However, the issue of high rxdrop/s affects anything, especially Oracle database performance, if it occurs on the database server.
In this post, I will explain the parameters that affect the behavior of receive packet drops per second (rxdrop/s).
The post is more about workarounds and tuning values rather than identifying exactly what has changed and why the fragmentation level has increased.
We will discuss several key /etc/sysctl.conf parameters that can help make fragmentation more manageable, these are:
net.ipv4.ipfrag_high_thresh = 67108864
net.ipv4.ipfrag_low_thresh = 66060288
net.ipv4.ipfrag_time = 10
The ksar graph (a tool that interprets output from sar) was displaying peaks for interface errors on eth1 interface, particularly rxdrop/s:
The following kernel parameters in Linux control how the system handles IP packet fragments in the IPv4 stack.
net.ipv4.ipfrag_high_thresh = 67108864When the total memory used for IP fragments exceeds 64 MB (67108864), the kernel will start dropping fragments until memory usage falls below the low threshold (ipfrag_low_thresh next parameter).
net.ipv4.ipfrag_low_thresh = 66060288Once memory drops below ~63 MB (66060288), fragment discarding stops.
net.ipv4.ipfrag_time = 10The default is often 30 seconds. Here it’s reduced to 10 seconds.
This helps prevent memory from being held too long by incomplete or malicious fragment streams, which are common in DoS attacks.
After changing these parameters in /etc/sysctl.conf you need to run sysctl -p to apply the modified kernel parameters and make them effective at runtime.
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