Time sync is always a good idea if for no other reason than being able to collate logs when debugging. Issues may also result if a client is expecting to reliably compare timestamps, ex. checking if a file has been modified. NTP is very easy to use.
Also of note: kerberos is very sensitive to clock skew if you intend to enable security. Daryn On Jun 5, 2013, at 12:59 AM, Harsh J wrote: > Skew in time between nodes is highly confusing, even if not a problem > to the runtime. I'd strongly recommend running a time sync service for > operational sanity. > > On Wed, Jun 5, 2013 at 8:41 AM, Chris Embree <[email protected]> wrote: >> Yes, NTPD is your best option. >> >> On 6/4/13, Ben Kim <[email protected]> wrote: >>> Hi, >>> This is very basic & fundamental question. >>> >>> Is time among all nodes needs to be synced? >>> >>> I've never even thought of timing in hadoop cluster but recently >>> experienced my servers going out of sync with time. I know hbase requires >>> time to by synced due to its timestamp action. But I wonder any of hadoop >>> functionality requires time sync. Perhaps checkpoint, namenode HA, or >>> datanode report, etc... hmm >>> >>> >>> -- >>> >>> *Benjamin Kim* >>> *benkimkimben at gmail* >>> > > > > -- > Harsh J
