When is it necessary to change the tape label

In the following cases it is necessary to change the labels by hand (how see next section).

• One wants to overwrite a tape (e.g. in the case the run crashes after 10 events and one has to restart from scratch).
• Multistreaming and one of the tape devices fails to open. The tape labels are ONLY done in the multistreaming format if all the tapes are opened at the same time. Therefore if only one of say four tape drives fails to open, one does not want to close and reopen the other three one. Instead one can open the tape that failed the first time individually and then adjust its label.