Nitin, You have the whole bunch of problems to answer/resolve.... Let me have some research first, then we can discuss the problem...
Thank you ! Leonid On Tue, May 14, 2013 at 12:43 AM, Nitin Pawar <nitinpawar...@gmail.com>wrote: > if you want to use savenamespace then yes. > > Normally to have a backup copy of the FSImage, previously there was a > secondary namenode and now there is checkpoint NN. SNN was deprecated but > later it was undeprecated > > the sole purpose of checkpoint NN is to have an rolling copy of the NN > based on interval you configure. > Checkpoint Node is the process which is actually responsible for creating > periodic check points. It downloads fsimage and log edits from the active > NameNode, merges them locally, and uploads the new image back to the active > NameNode. > > It is also a good practice that you configure multiple directories for > saving fsimage and editlogs on different disks. (From cloudera blog: By > storing two copies of the edit log and FSImage, on two separate hard disks, > a good system administrator can avoid bringing down the NameNode if one of > those disks fails.) > > > > > On Tue, May 14, 2013 at 12:57 PM, Sandeep Nemuri <nhsande...@gmail.com>wrote: > >> Done Lets say 8hrs !! >> now every 8hrs do we need to go into safemode ? >> >> >> On Tue, May 14, 2013 at 12:53 PM, Nitin Pawar <nitinpawar...@gmail.com>wrote: >> >>> every 5 minutes seems too much. >>> >>> why not do a daily or say 8 hours basis >>> >>> >>> On Tue, May 14, 2013 at 12:51 PM, Sandeep Nemuri >>> <nhsande...@gmail.com>wrote: >>> >>>> I Agree with you Nitin .. >>>> My Requirement is i want to copy the edits and fsimage from memory for >>>> every 5mins. How does this works ? >>>> >>>> >>>> On Tue, May 14, 2013 at 12:31 PM, Nitin Pawar >>>> <nitinpawar...@gmail.com>wrote: >>>> >>>>> if you do not put namenode in safemode that means your namenode can >>>>> still accept request to write or delete files from hdfs. This may cause >>>>> your snapshot to be a problematic in case you want to restore from it. >>>>> Safemode is just an ensuring point that you have a standstill image to >>>>> snapshot. >>>>> >>>>> >>>>> >>>>> >>>>> On Tue, May 14, 2013 at 12:27 PM, Sandeep Nemuri <nhsande...@gmail.com >>>>> > wrote: >>>>> >>>>>> Withuot going to safemode can't we get the Namespace ?? >>>>>> >>>>>> >>>>>> On Tue, May 14, 2013 at 12:18 PM, Ling Kun <lkun.e...@gmail.com>wrote: >>>>>> >>>>>>> Hi Aditya: >>>>>>> This command line may help you: >>>>>>> >>>>>>> hadoop dfsadmin --saveNamespace >>>>>>> >>>>>>> you should firstly perform it in safe mode. >>>>>>> >>>>>>> The corresponding design and implementation is described here: >>>>>>> https://issues.apache.org/jira/browse/HADOOP-4826 >>>>>>> >>>>>>> >>>>>>> yours, >>>>>>> Ling Kun >>>>>>> >>>>>>> >>>>>>> >>>>>>> On Tue, May 14, 2013 at 2:37 PM, Aditya exalter < >>>>>>> adityaexal...@gmail.com> wrote: >>>>>>> >>>>>>>> Hi, >>>>>>>> >>>>>>>> How to get the namenode data(edits and fsimage) from the main >>>>>>>> memory(RAM) >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>> >>>>>>> >>>>>>> -- >>>>>>> http://www.lingcc.com >>>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> --Regards >>>>>> Sandeep Nemuri >>>>>> >>>>> >>>>> >>>>> >>>>> -- >>>>> Nitin Pawar >>>>> >>>> >>>> >>>> >>>> -- >>>> --Regards >>>> Sandeep Nemuri >>>> >>> >>> >>> >>> -- >>> Nitin Pawar >>> >> >> >> >> -- >> --Regards >> Sandeep Nemuri >> > > > > -- > Nitin Pawar >
