Entering ROMMON Mode Power ON the switch and the press the MODE Button (1) ONLY when you see “System LED” is rapidly blinking. Pressing and holding the MODE button on startup WILL NOT WORK. Reference: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst9300/hardware/install/b_c9300_hig/b_c9300_hig_chapter_01001.html Setting up manual boot variable Password Reset Reference: https://community.cisco.com/t5/switching/c9300-switch-reset-to-factory/td-p/3358278