Home | About | Sematext search-lucene.com search-hadoop.com
 Search Hadoop and all its subprojects:

Switch to Threaded View
Hadoop >> mail # user >> how to get the time of a hadoop cluster, v0.20.2

Copy link to this message
Re: how to get the time of a hadoop cluster, v0.20.2
For hadoop, 'cluster time' is the local OS time. You might want to get the
time of the namenode machine but indeed if NTP is correctly used, the local
OS time from your server machine will be the best estimation. If you
request the time from the namenode machine, you will be penalized by the
delay of your request.


On Fri, May 17, 2013 at 3:17 PM, Niels Basjes <[EMAIL PROTECTED]> wrote:

> Hi,
> > i have another computer (which i have referred to as a server, since it
> is
> > running tomcat), and this computer is NOT a part of the hadoop cluster
> (it
> > doesn't run any of the hadoop daemons), but does submit jobs to the
> hadoop
> > cluster via a JEE webapp interface. i need to check that the time on this
> > computer is in sync with the time on the hadoop cluster. when i say
> "check
> > that the time is in sync", there is a defined tolerance/threshold
> > difference in date/time that i am willing to accept (e.g. the date/time
> > should be the same down to the minute).
> If you ensure (using NTP) that all your servers have the same time then you
> can simply query your local server for the time and you have the correct
> answer to your question.
> You are searching for a solution in the Hadoop API (where this does not
> exist) when the solution is present at a different level.
> --
> Best regards / Met vriendelijke groeten,
> Niels Basjes