Thanks for all the useful comments. On Thu, Mar 31, 2016 at 11:22 PM, Brice Dutheil <brice.duth...@gmail.com> wrote:
> Hi another tip, make sure the OS doesn't come with pre-configured NTP > synchronisation services. We had a proper NTP setup, but we missed a > service that came with CentOS that synced to a low stratum NTP server. > > -- Brice > > > > > On Thu, Mar 31, 2016 at 10:00 AM -0700, "Eric Evans" <eev...@wikimedia.org > > wrote: > > On Wed, Mar 30, 2016 at 8:07 PM, Mukil Kesavan wrote: >> > Are there any issues if this causes a huge time correction on the cassandra >> > cluster? I know that NTP gradually corrects the time on all the servers. I >> > just wanted to understand if there were any corner cases that will cause us >> > to lose data/schema updates when this happens. In particular, we seem to be >> > having some issues around missing secondary indices at the moment (not all >> > but some). >> >> As a thought experiment, imagine every scenario where it matters to >> have one write occur after another (an update followed by a delete is >> a good example). Now imagine having your clock yanked backward to >> correct for drift between the first such operation and the second. >> >> I would strongly recommend you come up with a stable NTP setup. >> >> >> -- >> Eric evanseev...@wikimedia.org >> >>
