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

Switch to Threaded View
Kafka, mail # user - partition reassignment


Copy link to this message
-
Re: partition reassignment
Kane Kane 2013-10-16, 07:30
Yes, thanks, looks like that's what i need, do you know why it tends to
choose the leader for all partitions on the single broker, despite I have 3?
On Wed, Oct 16, 2013 at 12:19 AM, Joel Koshy <[EMAIL PROTECTED]> wrote:

> Did the reassignment complete? If the assigned replicas are in ISR and
> the preferred replicas for the partitions are evenly distributed
> across the brokers (which seems to be a case on a cursory glance of
> your assignment) you can use this tool:
>
> https://cwiki.apache.org/confluence/display/KAFKA/Replication+tools#Replicationtools-2.PreferredReplicaLeaderElectionTool
>
> On Wed, Oct 16, 2013 at 12:15 AM, Kane Kane <[EMAIL PROTECTED]> wrote:
> > Oh i see, what is the better way to initiate the leader change? As I told
> > somehow all my partitions have the same leader for some reason. I have 3
> > brokers and all partitions have leader on single one.
> >
> >
> > On Wed, Oct 16, 2013 at 12:04 AM, Joel Koshy <[EMAIL PROTECTED]>
> wrote:
> >
> >> For a leader change yes, but this is partition reassignment which
> >> completes when all the reassigned replicas are in sync with the
> >> original replica(s). You can check the status of the command using the
> >> option I mentioned earlier.
> >>
> >> On Tue, Oct 15, 2013 at 7:02 PM, Kane Kane <[EMAIL PROTECTED]>
> wrote:
> >> > I thought if i have all replicas in sync, leader change should be much
> >> > faster?
> >> >
> >> >
> >> > On Tue, Oct 15, 2013 at 5:12 PM, Joel Koshy <[EMAIL PROTECTED]>
> wrote:
> >> >
> >> >> Depending on how much data there is in those partitions it can take a
> >> >> while for reassignment to actually complete. You will need to use the
> >> >> --status-check-json-file option of the reassign partitions command to
> >> >> determine whether partition reassignment has completed or not.
> >> >>
> >> >> Joel
> >> >>
> >> >>
> >> >> On Tue, Oct 15, 2013 at 3:46 PM, Kane Kane <[EMAIL PROTECTED]>
> >> wrote:
> >> >> > I have 3 brokers and a topic with replication factor of 3.
> >> >> > Somehow all partitions ended up being on the same broker.
> >> >> > I've created topic with 3 brokers alive, and they didn't die since
> >> then.
> >> >> >
> >> >> > Even when i try to reassign it:
> >> >> > bin/kafka-reassign-partitions.sh --zookeeper
> >> >> > 10.80.42.147:2181--broker-list 0,1,2 --topics-to-move-json-file
> >> >> > ~/reassign.txt --execute
> >> >> >
> >> >> > The leader of all partitions after that is still the single broker
> >> (first
> >> >> > one).
> >> >> > This is how my json file looks like:
> >> >> > {"topics":
> >> >> >                                             [{"topic": "perf1"}],
> >> >> >                                         "version":1
> >> >> >                                         }
> >> >> >
> >> >> > The command reports success:
> >> >> > Successfully started reassignment of partitions Map([perf1,33] ->
> >> List(1,
> >> >> > 0, 2), [perf1,13] -> List(2, 0, 1), [perf1,28] -> List(2, 1, 0),
> >> >> [perf1,20]
> >> >> > -> List(0, 1, 2), [perf1,5] -> List(0, 2, 1), [perf1,14] ->
> List(0, 1,
> >> >> 2),
> >> >> > [perf1,39] -> List(1, 0, 2), [perf1,19] -> List(2, 0, 1),
> [perf1,25]
> >> ->
> >> >> > List(2, 0, 1), [perf1,43] -> List(2, 0, 1), [perf1,11] -> List(0,
> 2,
> >> 1),
> >> >> > [perf1,8] -> List(0, 1, 2), [perf1,22] -> List(2, 1, 0),
> [perf1,16] ->
> >> >> > List(2, 1, 0), [perf1,26] -> List(0, 1, 2), [perf1,41] -> List(0,
> 2,
> >> 1),
> >> >> > [perf1,9] -> List(1, 0, 2), [perf1,27] -> List(1, 0, 2),
> [perf1,44] ->
> >> >> > List(0, 1, 2), [perf1,34] -> List(2, 1, 0), [perf1,6] -> List(1, 2,
> >> 0),
> >> >> > [perf1,1] -> List(2, 0, 1), [perf1,37] -> List(2, 0, 1),
> [perf1,24] ->
> >> >> > List(1, 2, 0), [perf1,29] -> List(0, 2, 1), [perf1,32] -> List(0,
> 1,
> >> 2),
> >> >> > [perf1,7] -> List(2, 0, 1), [perf1,17] -> List(0, 2, 1),
> [perf1,36] ->
> >> >> > List(1, 2, 0), [perf1,0] -> List(1, 2, 0), [perf1,42] -> List(1, 2,
> >> 0),
> >> >> > [perf1,4] -> List(2, 1, 0), [perf1,10] -> List(2, 1, 0),