Is there any how tos / examples which explains tape controlling (i.e. moving tapes, if first tape finished then instructing to choose the second etc.) through Data ONTAP mt command? Because, I want to automate certain things via scripts
There are no robot commands available from ONTAP... mt can rewind, forward on a tape already in a drive but haven't seen that used for backup. NDMP does pass through robot commands to the changer though but that is from external software... you could look at writing a script on a host to do this and use ndmp to pass those commands to the library around dump commands (7-Mode)... I remember someone posting something a while ago using some open source software but looked a bit mad science. There are several backup vendors that have already have done the work so would check the best deal you can get on NDMP software if budget is tight.
Years ago one of my customers wrote their own backup jobs using MTX tools… http://sourceforge.net/projects/mtx/ open source but they scripted ndmp calls around it and was a cool science project. Not something for an enterprise but if no way to purchase software this might be the way to go.