Hi,

We run a 3 server cassandra cluster that is initially NTP synced to a
single physical server over LAN. This server does not have connectivity to
the internet for a few hours to sometimes even days. In this state we
perform some schema operations and reads/writes with QUORUM consistency.

Later on, the physical server has connectivity to the internet and we
synchronize its time to an external NTP server on the internet.

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).

Also, for our situation where we have to work with cassandra for a while
without internet connectivity, what is the preferred NTP architecture/steps
that have worked for you in the field?

Thanks,
Micky

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