There are two methods to configure/tune the Kernel parameters in RHEL
1. Use the command sysctl -w <parameter_name>= <value>
The above command will change the kernel parameters on the fly but the changes are not persistent with system reboots.
2. The second method is,
a. Edit the file "/etc/sysctl.conf" by adding the parameters along with values
b. execute "/sbin/sysctl -p" to make sure that the changes are made using the values inside the above mentioned file.
The advantage with the second method is that the changes are persistent with system reboots.
To View the Kernel Parameters:
Hope that the information will be useful for you.