When "TransportError Signature not yet current ..." appears in ElasticSearch (AWS ESS)

TransportError(403, '{"message":"Signature not yet current: 20170412T064759Z is still later than 20170412T064642Z (20170412T064142Z + 5 min.)"}')

If you encounter this issue, it is likely that the server's clock is not synchronized properly.

$ sudo apt install ntpdate
$ sudo ntpdate clock.nc.fukuoka-u.ac.jp

Try synchronizing the time like this.