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date +%T -s "11:14:00" timedatectl set-time "2018-10-06 10:35:00"
$ date $ date -u $ date '+%Y-%m-%d_%H:%M:%S'
$ date -v-1d '+%Y.%m.%d'
$ date --date "1 day ago" +%Y-%m-%d $ date --date "1 hour ago" "+%Y-%m-%d %H"