ORA-15120: ASM file name ‘ORA-27090: Unable to reserve kernel resources f’ does not begin with the ASM prefix character
March 24, 2022 Leave a comment
Problem:
The customer created 36 databases on the same server and while creating the 37th using dbca got the following error:

Reason:
fs.aio-max-nr
value was set too low in /etc/sysctl.conf. In general, value 3145728 that was set in their case, suits many environments, but if the number of databases on the server increases then this parameter should be adjusted accordingly.
Solution:
The formula used while calculating the value for this parameter is the following:
aio-max-nr = no of process per DB * no of databases * 4096
In their case, the number of processes per DB was 1000, the number of databases that planned to be created was 80. Based on the above value should be:
aio-max-nr = 327680000
- Add/update value in /etc/sysctl.conf:
# vim /etc/sysctl.conf fs.aio-max-nr = 327680000
2. Run /sbin/sysctl -p to immediately enforce the changes:
# sysctl -p
Delete already created files and recreate the database, it will succeed this time.