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

Switch to Threaded View
Hadoop >> mail # user >> Re:HDFS start-up with safe mode?


Copy link to this message
-
Re: Re:HDFS start-up with safe mode?
I modify the value of "dfs.safemode.threshold.pct" to zero, now everything is ok.
log file as below
But there are still three questions

  1.. Can I regain percentage of blocks that should satisfy the minimal replication requirement
          to 99.9%?  hadoop balancer? For I feel it will be more safe.

    2.   I set "dfs.safemode.threshold.pct" to "0" or "0f", two value both work, but which one is
          better?  I guess "0"

    3.   When HDFS start up in safe mode, the log file should show
          "The reported blocks 0 needs additional 2 blocks to reach the threshold 0.9990 of total blocks 3. Safe mode will 'not' be turned off automatically."
         There miss a word "not" , right?

Ring

/************************************************************

SHUTDOWN_MSG: Shutting down NameNode at computeb-05.pcm/172.172.2.6

************************************************************/

2011-04-08 16:33:37,312 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: STARTUP_MSG:

/************************************************************

STARTUP_MSG: Starting NameNode

STARTUP_MSG:   host = computeb-05.pcm/172.172.2.6

STARTUP_MSG:   args = []

STARTUP_MSG:   version = 0.20.2-CDH3B4

STARTUP_MSG:   build =  -r 3aa7c91592ea1c53f3a913a581dbfcdfebe98bfe; compiled by 'root' on Mon Feb 21 17:31:12 EST 2011

************************************************************/

2011-04-08 16:33:37,441 INFO org.apache.hadoop.metrics.jvm.JvmMetrics: Initializing JVM Metrics with processName=NameNode, sessionId=null

2011-04-08 16:33:37,443 INFO org.apache.hadoop.hdfs.server.namenode.metrics.NameNodeMetrics: Initializing NameNodeMeterics using context object:org.apache.hadoop.metrics.spi.NullContext

2011-04-08 16:33:37,464 INFO org.apache.hadoop.hdfs.util.GSet: VM type       = 32-bit

2011-04-08 16:........................................
2011-04-08 16:33:37,832 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Number of under-replicated blocks = 4

2011-04-08 16:33:37,832 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Number of  over-replicated blocks = 0

2011-04-08 16:33:37,832 INFO org.apache.hadoop.hdfs.StateChange: STATE* Leaving safe mode after 0 secs.

2011-04-08 16:33:37,832 INFO org.apache.hadoop.hdfs.StateChange: STATE* Network topology has 0 racks and 0 datanodes

2011-04-08 16:33:37,832 INFO org.apache.hadoop.hdfs.StateChange: STATE* UnderReplicatedBlocks has 4 blocks

2011-04-08 16:33:37,835 INFO org.apache.hadoop.util.HostsFileReader: Refreshing hosts (include/exclude) list

2011-04-08 16:33:37,849 INFO org.apache.hadoop.ipc.Server: Starting Socket Reader #1 for port 9100

----- Original Message -----
From: "springring" <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Cc: <[EMAIL PROTECTED]>
Sent: Friday, April 08, 2011 3:45 PM
Subject: Re:HDFS start-up with safe mode?
> Hi,
>
>    I guess that something about "threshold 0.9990". When HDFS start up,
> it come in safe mode first, then check a value(I don't know what value or percent?)
> of my hadoop,and fine the value below 99.9%,  so the safe mode will not turn off?
>
> but the conclusion of the log file is "Safe mode will be turned off automatically"?
>
> I'm lost.
> ___________________________________________________
> 2011-04-08 11:58:21,036 INFO org.apache.hadoop.hdfs.StateChange: STATE* Safe mode ON.
>>>> The reported blocks 0 needs additional 2 blocks to reach the threshold 0.9990 of total blocks 3. Safe mode will be turned off automatically.
> ________________________________________________________________________
>
> ----- Original Message -----
> From: "springring" <[EMAIL PROTECTED]>
> To: <[EMAIL PROTECTED]>
> Sent: Friday, April 08, 2011 2:20 PM
> Subject: Fw: start-up with safe mode?
>
>
>>
>>
>>>
>>>> Hi,
>>>>
>>>>   When I start up hadoop, the namenode log show "STATE* Safe mode ON" like that , how to set it off?
>>>     I can set it off with command "hadoop fs -dfsadmin leave" after start up, but how can I just start HDFS