the clock is about 30 to 40 seconds behind. From: Jack Krupansky <jack.krupan...@gmail.com> To: user@cassandra.apache.org Sent: Wednesday, March 9, 2016 11:31 AM Subject: Re: ntpd clock sync How far out of sync are the nodes? A few minutes or less? Many hours? Worst case, you could simply take the entire cluster down until that future time has passed and then bring it back up.
-- Jack Krupansky On Wed, Mar 9, 2016 at 11:27 AM, Jeff Jirsa <jeff.ji...@crowdstrike.com> wrote: If you don’t overwrite or delete data, it’s not a concern.If the clocks show a time in the past instead of in the future, it’s not a concern. If the clock has drifted significantly into the future, when you start NTP you may be writing data with timestamps lower than timestamps on data that already exists. In this case, the existing data (with timestamps in the future) may take precedence over new writes (with correct timestamps). From: K F Reply-To: "user@cassandra.apache.org", K F Date: Wednesday, March 9, 2016 at 8:23 AM To: User Subject: ntpd clock sync Hi, I have question about ntpd. In certain clusters where new datacenters were added since 1 week we stood-up those machines didn't have ntpd running on them. Will it cause any problem if we enable or start ntpd now on those newly added datacenters. Thanks.