not at all. so don't worry about that.
On Wed, Apr 3, 2013 at 2:04 PM, Yanbo Liang <yanboha...@gmail.com> wrote: > It means that may be some replicas will be stay in under replica state? > > > 2013/4/3 Azuryy Yu <azury...@gmail.com> > >> bq. then namenode start to copy block replicates on DN-2 to another DN, >> supposed DN-2. >> >> sorry for typo. >> >> Correct for it: >> then namenode start to copy block replicates on DN-1 to another DN, >> supposed DN-2. >> >> >> On Wed, Apr 3, 2013 at 9:51 AM, Azuryy Yu <azury...@gmail.com> wrote: >> >>> It's different. >>> If you just want to stop DN-1 a short time, just kill the DataNode >>> process on DN-1. then do what you want. during this time, Namenode cannot >>> receive the heart beat from DN-1, then namenode start to copy block >>> replicates on DN-2 to another DN, supposed DN-2. >>> >>> But when you start DN-1 again, Namenode receive the DN-1 registration, >>> then namenode stop to copy the DN-1's block replicates even if NN doesn't >>> finish coping. >>> >>> Am I explain clearly? >>> >>> >>> >>> On Wed, Apr 3, 2013 at 9:43 AM, Henry Junyoung Kim < >>> henry.jy...@gmail.com> wrote: >>> >>>> @Harsh >>>> >>>> What's the reasons to make big gaps for removing nodes between >>>> decommission and just down nodes? >>>> In my understanding, both are necessary to copy un-replicated blocks to >>>> another alive nodes. >>>> If main costs of them are this one, total elapsed time couldn't be big >>>> different. >>>> >>>> Could you share some articles or documents to understand about >>>> decommissioning procedures? >>>> - explaining is always thanks ;) >>>> >>>> >>>> 2013. 4. 2., 오후 5:37, Harsh J <ha...@cloudera.com> 작성: >>>> >>>> > Yes, you can do the downtime work in steps of 2 DNs at a time, >>>> > especially since you mentioned the total work would be only ~30mins at >>>> > most. >>>> > >>>> > On Tue, Apr 2, 2013 at 1:46 PM, Henry Junyoung Kim >>>> > <henry.jy...@gmail.com> wrote: >>>> >> the rest of nodes to be alive has enough size to store. >>>> >> >>>> >> for this one that you've mentioned. >>>> >>> its easier to do so in a rolling manner without need of a >>>> >>> decommission. >>>> >> >>>> >> to check my understanding, just shutting down 2 of them and then 2 >>>> more and then 2 more without decommissions. >>>> >> >>>> >> is this correct? >>>> >> >>>> >> >>>> >> 2013. 4. 2., 오후 4:54, Harsh J <ha...@cloudera.com> 작성: >>>> >> >>>> >>> Note though that its only possible to decommission 7 nodes at the >>>> same >>>> >>> time and expect it to finish iff the remaining 8 nodes have adequate >>>> >>> free space for the excess replicas. >>>> >>> >>>> >>> If you're just going to take them down for a short while (few mins >>>> >>> each), its easier to do so in a rolling manner without need of a >>>> >>> decommission. You can take upto two down at a time on a replication >>>> >>> average of 3 or 3+, and put it back in later without too much data >>>> >>> movement impact. >>>> >>> >>>> >>> On Tue, Apr 2, 2013 at 1:06 PM, Yanbo Liang <yanboha...@gmail.com> >>>> wrote: >>>> >>>> It's reasonable to decommission 7 nodes at the same time. >>>> >>>> But may be it also takes long time to finish it. >>>> >>>> Because all the replicas in these 7 nodes need to be copied to >>>> remaining 8 >>>> >>>> nodes. >>>> >>>> The size of transfer from these nodes to the remaining nodes is >>>> equal. >>>> >>>> >>>> >>>> >>>> >>>> 2013/4/2 Henry Junyoung Kim <henry.jy...@gmail.com> >>>> >>>>> >>>> >>>>> :) >>>> >>>>> >>>> >>>>> currently, I have 15 data nodes. >>>> >>>>> for some tests, I am trying to decommission until 8 nodes. >>>> >>>>> >>>> >>>>> Now, the total dfs used size is 52 TB which is including all >>>> replicated >>>> >>>>> blocks. >>>> >>>>> from 15 to 8, total spent time is almost 4 days long. ;( >>>> >>>>> >>>> >>>>> someone mentioned that I don't need to decommission node by node. >>>> >>>>> for this case, is there no problems if I decommissioned 7 nodes >>>> at the >>>> >>>>> same time? >>>> >>>>> >>>> >>>>> >>>> >>>>> 2013. 4. 2., 오후 12:14, Azuryy Yu <azury...@gmail.com> 작성: >>>> >>>>> >>>> >>>>> I can translate it to native English: how many nodes you want to >>>> >>>>> decommission? >>>> >>>>> >>>> >>>>> >>>> >>>>> On Tue, Apr 2, 2013 at 11:01 AM, Yanbo Liang < >>>> yanboha...@gmail.com> wrote: >>>> >>>>>> >>>> >>>>>> You want to decommission how many nodes? >>>> >>>>>> >>>> >>>>>> >>>> >>>>>> 2013/4/2 Henry JunYoung KIM <henry.jy...@gmail.com> >>>> >>>>>>> >>>> >>>>>>> 15 for datanodes and 3 for replication factor. >>>> >>>>>>> >>>> >>>>>>> 2013. 4. 1., 오후 3:23, varun kumar <varun....@gmail.com> 작성: >>>> >>>>>>> >>>> >>>>>>>> How many nodes do you have and replication factor for it. >>>> >>>>>>> >>>> >>>>>> >>>> >>>>> >>>> >>>>> >>>> >>>> >>>> >>> >>>> >>> >>>> >>> >>>> >>> -- >>>> >>> Harsh J >>>> >> >>>> > >>>> > >>>> > >>>> > -- >>>> > Harsh J >>>> >>>> >>> >> >
