The primary keyword to start a loop that will iterate a fixed number of times in shell scripting is for. The for loop allows you to specify the number of iterations and is commonly used for such purposes.

The command 'lsmod' is used to list currently loaded kernel modules in Linux. This command displays a list of all the kernel modules that are currently loaded into the running kernel.

The while loop in shell scripting tests the condition before executing the body of the loop. It will repeatedly execute the loop body as long as the specified condition remains true.

In Linux, services that are set to restart automatically after a failure are said to be "Autorestart." This feature ensures that critical services can recover from failures and continue running, enhancing system reliability and availability.