$cat tt.sh
#!/bin/bash
start=`date +%s -d "2017-02-27 00:00:00"`
end=`date +%s -d "2017-02-28 00:00:00"`
while [ "$start" -le "$end" ]
do
day=`date -d @$start "+%Y%m%d"`
echo $day
start=$((start+86400))
done
$cat tt.sh
#!/bin/bash
start=`date +%s -d "2017-02-27 00:00:00"`
end=`date +%s -d "2017-02-28 00:00:00"`
while [ "$start" -le "$end" ]
do
day=`date -d @$start "+%Y%m%d"`
echo $day
start=$((start+86400))
done