Controlling network traffic from client schedules

You can control the network traffic from scheduled client operations by using certain Tivoli® Storage Manager server SET commands. The commands control how frequently clients contact the server, and how the sessions are spread across the schedule window.

• Use the SET RANDOMIZE command to randomize start times within the startup window of each client schedule. Communication errors can happen when many clients contacts the server simultaneously. If concurrent scheduled operations for clients have communication errors, you can increase the randomization percentage so that client contact is spread out. Increased randomization decreases the chance for communication overload and failure. The randomized start times apply only to clients that use the client-polling scheduling mode.
• Set how frequently a client can contact the server to obtain scheduled work by using the SET QUERYSCHEDPERIOD command. This command overrides the client setting, and applies when the client-polling mode is used for schedules. A shorter time period means more network traffic because of client polling. Use longer settings (6 - 12 hours) to reduce network traffic. Alternately, use the server-prompted scheduling mode to eliminate network traffic because of client polling.
• Set a global limit on the number of times that a scheduled command is tried again on a client by using the SET MAXCMDRETRIES command. This command overrides the client setting. A smaller number reduces network traffic that is caused by scheduled commands that are tried again.

  If you use the SET MAXCMDRETRIES command, be sure to consider schedule startup windows. If a retry is attempted outside of the schedule startup window, it fails.

• Set the number of minutes between retries of a scheduled command after a failed attempt to contact the server. Use the SET RETRYPERIOD command. This command overrides the client setting. A larger value reduces the network traffic that is caused by retries and increases the chance of a successful retry.

  If you use the SET RETRYPERIOD command, be sure to consider schedule startup windows. If a retry is attempted outside of the schedule startup window, it fails.