Display Kernel Parameter Values for Red-hat Linux (RHEL 9)

 

Command to see Kernel Parameter Values 

Parameter	Command
semmsl, semmns, semopm, and semmni	# /sbin/sysctl -a | grep sem This command displays the value of the semaphore parameters in the order listed.
shmall, shmmax, and shmmni	# /sbin/sysctl -a | grep shm This command displays the details of the shared memory segment sizes.
file-max	# /sbin/sysctl -a | grep file-max This command displays the maximum number of file handles.
ip_local_port_range	# /sbin/sysctl -a | grep ip_local_port_range This command displays a range of port numbers.
rmem_default	# /sbin/sysctl -a | grep rmem_default
rmem_max	# /sbin/sysctl -a | grep rmem_max
wmem_default	# /sbin/sysctl -a | grep wmem_default
wmem_max	# /sbin/sysctl -a | grep wmem_max
aio-max-nr	# /sbin/sysctl -a | grep aio-max-nr

Minimum Kernel Parameter Settings for Oracle Database 19c Installation - Redhat Linux

 

For Oracle Database kernel parameter and shell limit values

Parameter	Value	File
semmsl semmns semopm semmni	250 32000 100 128	/proc/sys/kernel/sem
shmall	Greater than or equal to the value of shmmax, in pages.	/proc/sys/kernel/shmall
shmmax	Half the size of physical memory in bytes See My Oracle Support Note 567506.1 for additional information about configuring shmmax.	/proc/sys/kernel/shmmax
shmmni	4096	/proc/sys/kernel/shmmni
panic_on_oops	1	/proc/sys/kernel/panic_on_oops
file-max	6815744	/proc/sys/fs/file-max
aio-max-nr	1048576 Note: This value limits concurrent outstanding requests and should be set to avoid I/O subsystem failures.	/proc/sys/fs/aio-max-nr
ip_local_port_range	Minimum: 9000 Maximum: 65500	/proc/sys/net/ipv4/ip_local_port_range
rmem_default	262144	/proc/sys/net/core/rmem_default
rmem_max	4194304	/proc/sys/net/core/rmem_max
wmem_default	262144	/proc/sys/net/core/wmem_default
wmem_max	1048576	/proc/sys/net/core/wmem_max

How to Initiate the AWS Oracle RDS Data Guard switchover using the AWS CLI

Switch primary to read replica (standby ) and vice-versa

AWS CLI :

aws rds switchover-read-replica --db-instance-identifier ora-orcl-demo2 --region us-west-2

aws rds switchover-read-replica --db-instance-identifier ora-orcl-demo1  --region us-east-1

aws rds describe-db-instances --db-instance-identifier ora-orcl-demo1 

AWS Link 

https://aws.amazon.com/blogs/database/managed-oracle-data-guard-switchover-with-amazon-rds-for-oracle/

AWS DMS Mapping Table (MSSQL) : Loading Table data using boundaries

 MSSQL query boundaries conditions  

SELECT Max(Id)  nt

FROM (SELECT Id,(Ntile(160) over( ORDER BY Id)) nt FROM demo)

test

GROUP BY nt

ORDER BY nt

option (maxDOP 1024)