Kashif J S created HBASE-9902:
---------------------------------

             Summary: Region Server is starting normally even if clock skew is 
more than default 30 seconds(or any configured). -> Regionserver node time is 
greater than master node time
                 Key: HBASE-9902
                 URL: https://issues.apache.org/jira/browse/HBASE-9902
             Project: HBase
          Issue Type: Bug
          Components: master
    Affects Versions: 0.94.11
            Reporter: Kashif J S


When Region server's time is ahead of Master's time and the difference is more 
than hbase.master.maxclockskew value, region server startup is not failing with 
ClockOutOfSyncException.
This causes some abnormal behavior as detected by our Tests.

    ServerManager.java#checkClockSkew
          long skew = System.currentTimeMillis() - serverCurrentTime;
        if (skew > maxSkew) {
          String message = "Server " + serverName + " has been " +
            "rejected; Reported time is too far out of sync with master.  " +
            "Time difference of " + skew + "ms > max allowed of " + maxSkew + 
"ms";
          LOG.warn(message);
          throw new ClockOutOfSyncException(message);
        }

    Above line results in negative value when Master's time is lesser than 
region server time and  " if (skew > maxSkew) " check fails to find the skew in 
this case.


    Please Note: This was tested in hbase 0.94.11 version and the trunk also 
currently has the same logic.

The fix for the same would be to make the skew positive value first as below:

 long skew = System.currentTimeMillis() - serverCurrentTime;
    skew = (skew < 0 ? -skew : skew);
    if (skew > maxSkew) {.....



--
This message was sent by Atlassian JIRA
(v6.1#6144)

Reply via email to