THese values would be correct for a Linux system. While your cell Manager is Linux, nothing is said about your clients he Disk Agent (the system being backed up), or the Media Agent, the system that controls the tape drive
Also, it is not enough to just implement the KeepAlive parameters, you also need to add OB2IPCKEEPALIVE=1 into the 'omnirc' file on each server
Finally, it was found out that OB2IPCKEEPALIVE was not working on Linux systems, this was fixed with the upgrade to DP 7.03. Since you are running DP 6.11, this fix will not apply to you