What's the difference between the three nouns? Are they used for different types of journaling?
日誌(にっし) is a log (or logbook) used to record states, events or conditions related to machines or processes by the people who operate or manage them, initially ships, but today also e.g. aircraft, nuclear plants, medical or dietary conditions, etc. The following page has instructions for how to keep a nursing log. https://job.mynavi.jp/conts/2024/tok/hoiku/know/training_diary/01.html
日記(にっき) usually refers to a personal diary. The following store offers related stationary. https://www.midori-store.net/SHOP/5293/list.html
日録(にちろく) is usually an official record. See for instance the following record of official duties at the Imperial Household Agency. https://www.kunaicho.go.jp/culture/shoryobu/syuzou-k05.html