mjhjmtu

I am looking to get a time range from a given time. The start time should be 60
mins before the given time and end time should be 60 mins after the given time.

Purpose:
The given time will be like an 'impact time', I am looking to get a suitable range of time around the impact time to be able to grab logs.

Example :
Given time is 2018-05-16 20:30:00
This is of the format '%Y-%m-%d %H:%M:%S'

Please help me get:
Start time is 2018-05-16 19:30:00
End time is 2018-05-16 21:30:00

This is going to run on a server that will be in PDT/PST always and the date-time is of the format '%Y-%m-%d %H:%M:%S'

Assuming the timezone is set correctly, and GNU date, you can get the Unix timestamp, subtract, add 60 minutes and convert it back to the format needed:

$ ts=$(date -d "2018-05-16 21:30:00" +%s) # For BSD date: date -jf "%F %T" "2018-05-16 21:30:00" +%s 
$ echo "$(date -d@$((ts - 3600)) +"%F %T")"
2018-05-16 20:30:00
$ echo "$(date -d@$((ts + 3600)) +"%F %T")"
2018-05-16 22:30:00

... I think this doesn't correctly account for leap seconds and various other problems every programmer should know about time.