[
https://issues.apache.org/jira/browse/KAFKA-3039?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16061326#comment-16061326
]
Sven Ludwig commented on KAFKA-3039:
------------------------------------
I just observed this on Confluent Platform 3.2.1 with Kafka 0.10.2.1
For 907 (including some offset topics) out of 1263 topics the broker logged on
restart:
{{INFO Truncating log <topic-partition> to offset 0. (kafka.log.Log)}}
During the broker's downtime, In this particular case, it was only missing
leader for exactly one partition. For all other partitions, other nodes were
the leader.
This gave me the chills and I immediately shutdown the broker again. Now there
is no missing leader. I do not know if data was lost.
> Temporary loss of leader resulted in log being completely truncated
> -------------------------------------------------------------------
>
> Key: KAFKA-3039
> URL: https://issues.apache.org/jira/browse/KAFKA-3039
> Project: Kafka
> Issue Type: Bug
> Components: core
> Affects Versions: 0.9.0.0
> Environment: Debian 3.2.54-2 x86_64 GNU/Linux
> Reporter: Imran Patel
> Priority: Critical
> Labels: reliability
>
> We had an event recently where the temporarily loss of a leader for a
> partition (during a manual restart), resulted in the leader coming back with
> no high watermark state and truncating its log to zero. Logs (attached below)
> indicate that it did have the data but not the commit state. How is this
> possible?
> Leader (broker 3)
> [2015-12-18 21:19:44,666] INFO Completed load of log messages-14 with log end
> offset 14175963374 (kafka.log.Log)
> [2015-12-18 21:19:45,170] INFO Partition [messages,14] on broker 3: No
> checkpointed highwatermark is found for partition [messages,14]
> (kafka.cluster.Partition)
> [2015-12-18 21:19:45,238] INFO Truncating log messages-14 to offset 0.
> (kafka.log.Log)
> [2015-12-18 21:20:34,066] INFO Partition [messages,14] on broker 3: Expanding
> ISR for partition [messages,14] from 3 to 3,10 (kafka.cluster.Partition)
> Replica (broker 10)
> [2015-12-18 21:19:19,525] INFO Partition [messages,14] on broker 10:
> Shrinking ISR for partition [messages,14] from 3,10,4 to 10,4
> (kafka.cluster.Partition)
> [2015-12-18 21:20:34,049] ERROR [ReplicaFetcherThread-0-3], Current offset
> 14175984203 for partition [messages,14] out of range; reset offset to 35977
> (kafka.server.ReplicaFetcherThread)
> [2015-12-18 21:20:34,033] WARN [ReplicaFetcherThread-0-3], Replica 10 for
> partition [messages,14] reset its fetch offset from 14175984203 to current
> leader 3's latest offset 35977 (kafka.server.ReplicaFetcherThread)
> Some relevant config parameters:
> offsets.topic.replication.factor = 3
> offsets.commit.required.acks = -1
> replica.high.watermark.checkpoint.interval.ms = 5000
> unclean.leader.election.enable = false
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
