--- Jim Kellerman, Senior Engineer; Powerset
> -----Original Message----- > From: Ipraveen [mailto:[EMAIL PROTECTED] > Sent: Wednesday, April 02, 2008 2:57 AM > To: [email protected] > Subject: RE: how to find out name node is running > > > hi > i dont understand what u are saying, > and still i am unable to find the namenode status, how would > i find where it is running? It is in the configuration. > and how to i get configuration > object that can have namenode refrences.? Configuration conf = new Configuration(); > > > > > Jim Kellerman wrote: > > > > What we do in HBase is the following: > > > > this.fs = FileSystem.get(conf); > > if (this.fs instanceof DistributedFileSystem) { > > // Make sure dfs is not in safe mode > > String message = "Waiting for dfs to exit safe mode..."; > > while (((DistributedFileSystem) fs).setSafeMode( > > FSConstants.SafeModeAction.SAFEMODE_GET)) { > > LOG.info(message); > > try { > > Thread.sleep(this.threadWakeFrequency); > > } catch (InterruptedException e) { > > //continue > > } > > } > > } > > > > In Hadoop 0.16, this will fail if you are running with privileges > > enabled and your application is not running as Superuser. However, > > querying the namenode state does not require privileges in > Hadoop 0.17 > > > > > > --- > > Jim Kellerman, Senior Engineer; Powerset > > > > > >> -----Original Message----- > >> From: Andy Li [mailto:[EMAIL PROTECTED] > >> Sent: Tuesday, March 25, 2008 11:54 PM > >> To: [email protected] > >> Subject: Re: how to find out name node is running > >> > >> I believe this class is the one you are looking for. > >> > >> org.apache.hadoop.dfs.namenode.metrics.NameNodeStatistics > >> > >> I just went through the API list from the website 0.16.0 and found > >> this one. > >> A blunt guess is that if you can invoke these method and get a > >> response, then you can probably assume the namenode is alive. But > >> you will need to do some code hacking to figure out how to > use it and > >> study it a little bit to understand what is going on underneath to > >> confirm. Just a reference. > >> > >> -Andy > >> > >> On Tue, Mar 25, 2008 at 11:16 PM, Ipraveen > <[EMAIL PROTECTED]> > >> wrote: > >> > >> > > >> > yes you are right Andy , i want to know is there is any > >> hadoop library > >> > api which can trace name node or datnode ? > >> > > >> > > >> > Andy Li-3 wrote: > >> > > > >> > > That's relying on Java Virtual Machine process status > >> tool, similar > >> > > to > >> > 'ps > >> > > aux|grep java' on a Linux? > >> > > > >> > > I think the question is whether there is any API from > >> Hadoop library > >> > which > >> > > can monitor the namenode > >> > > through a Java API without relying 3rd party utility > >> tool. Am I right? > >> > > > >> > > -Andy > >> > > > >> > > On Tue, Mar 25, 2008 at 6:26 AM, Zhu Huijun > >> > > <[EMAIL PROTECTED]> > >> > wrote: > >> > > > >> > >> Type the command "jps" in your command window. If your > >> name node is > >> > >> running, there will be an output item of "Namenode". Or > >> check the > >> > >> web page at http://localhost:50070 if you did not change the > >> > >> default server host > >> > and > >> > >> port of the web. > >> > >> > >> > >> 2008/3/25, Ipraveen <[EMAIL PROTECTED]>: > >> > >> > > >> > >> > > >> > >> > hi > >> > >> > how would i know whether a name node is runnning or not? > >> > >> > by using hadoop API for java. > >> > >> > > >> > >> > regards > >> > >> > praveen jain > >> > >> > -- > >> > >> > View this message in context: > >> > >> > > >> > >> > >> > > >> > http://www.nabble.com/how-to-find-out-name-node-is-running-tp16274770 > >> p > >> > 16274770.html > >> > >> > Sent from the Hadoop core-dev mailing list archive at > >> Nabble.com. > >> > >> > > >> > >> > > >> > >> > >> > > > >> > > > >> > > >> > -- > >> > View this message in context: > >> > > >> > http://www.nabble.com/how-to-find-out-name-node-is-running-tp16274770 > >> p > >> > 16296276.html Sent from the Hadoop core-dev mailing list > archive at > >> > Nabble.com. > >> > > >> > > >> > >> No virus found in this incoming message. > >> Checked by AVG. > >> Version: 7.5.519 / Virus Database: 269.22.0/1344 - Release > >> Date: 3/26/2008 8:52 AM > >> > >> > > > > No virus found in this outgoing message. > > Checked by AVG. > > Version: 7.5.519 / Virus Database: 269.22.0/1344 - Release Date: > > 3/26/2008 > > 8:52 AM > > > > > > > > -- > View this message in context: > http://www.nabble.com/how-to-find-out-name-node-is-running-tp1 > 6274770p16446350.html > Sent from the Hadoop core-dev mailing list archive at Nabble.com. > > > No virus found in this incoming message. > Checked by AVG. > Version: 7.5.519 / Virus Database: 269.22.4/1355 - Release > Date: 4/1/2008 5:37 PM > > No virus found in this outgoing message. Checked by AVG. Version: 7.5.519 / Virus Database: 269.22.4/1355 - Release Date: 4/1/2008 5:37 PM
