Founder Thilo Kuther continues to serve as president and exec producer. He originally called this processor COMMAND, later named EXEC. The exec command can also perform a redirection. A single Backup Exec server is assigned the standalone Backup Exec server role. VMS defines four privilege levels&colon; user, supervisor, exec, and kernel. Problems start from board and exec management. Newly compiled commands then become functionally part of the EXEC. Thus, in these situations, Exec Shield's schemes fails. The Exec and the file backup system are fully integrated. AmigaOS is a single-user operating system based on a preemptive multitasking kernel, called Exec. The heart of the Exec is the Dispatcher which manages all the processors. Installing Backup Exec 15 on a Windows Server 2012 R2 system takes around 30 minutes. The PaX and Exec Shield patchsets to the Linux kernel provide more complete implementations. Higher-level languages usually provide one call named exec. The Exec itself is largely structured as a real time program.