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 - `HOSTNAME` Server you would like to continuously ping [ default=localhost ]
 - `PING_PERIOD` Number of second between each ping
 - `TIMEOUT` Number of seconds before timeout during curl request [ default=3 ]
+- `FAIL_PERIOD` Number of seconds before notifying that server is fail
 - `SLACK_TOKEN` slack access token
 - `SLACK_CHANNEL` slack channel to be send to [ default="#ci_cd_webhook"]