This is strange, the retry strategy was 20 times with 4 minute delay. This job tried once ( we had a hadoop Name Node hiccup ) but I think it could not even get to NN and gave up ( as in did not retry the next 19 times ) ....
*019-06-29 00:33:13,680 INFO org.apache.flink.runtime.executiongraph.ExecutionGraph - Could not restart the job Kafka-to-HDFS (00000000000000000000000000000005) because the restart strategy prevented it.* On Sat, Jun 29, 2019 at 10:03 AM Vishal Santoshi <vishal.santo...@gmail.com> wrote: > We are investigating that. But is the above theory plausible ( flink > gurus ) even though this, as in forcing restartPolicy: Never pretty much > nullifies HA on JM is it is a Job cluster ( at leats on k8s ) > > > As for the reason we are investigating that. > > One thing we looking as the QOS ( > https://kubernetes.io/docs/tasks/configure-pod-container/quality-service-pod/ > ) > , which was Burstable, a limit was not set on the job. The below for > example would have a QOS of guaranteed. So one reason could be this. > > resources: > requests: > cpu: "8.0" > memory: "16Gi" > limits: > cpu: "8.0" > memory: "16Gi" > > > > > > On Sat, Jun 29, 2019 at 9:35 AM Timothy Victor <vict...@gmail.com> wrote: > >> This is slightly off topic, so I'm changing the subject to not conflate >> the original issue you brought up. But do we know why JM crashed in the >> first place? >> >> We are also thinking of moving to K8s, but to be honest we had tons of >> stability issues in our first rodeo. That could just be our lack of a >> deeper understanding of K8s (a lot had to do with DNS). But cases like >> this make me wonder what happened to cause the crash in the first place. >> >> Thanks >> >> Tim >> >> >> On Sat, Jun 29, 2019, 8:25 AM Vishal Santoshi <vishal.santo...@gmail.com> >> wrote: >> >>> Another point the JM had terminated. The policy on K8s for Job Cluster is >>> >>> spec: >>> restartPolicy: OnFailure >>> >>> >>> *2019-06-29 00:33:14,308 INFO >>> org.apache.flink.runtime.entrypoint.ClusterEntrypoint - Terminating cluster >>> entrypoint process StandaloneJobClusterEntryPoint with exit code 1443.* >>> >>> >>> >>> On Sat, Jun 29, 2019 at 9:04 AM Vishal Santoshi < >>> vishal.santo...@gmail.com> wrote: >>> >>>> I have not tried on bare metal. We have no option but k8s. >>>> >>>> And this is a job cluster. >>>> >>>> On Sat, Jun 29, 2019 at 9:01 AM Timothy Victor <vict...@gmail.com> >>>> wrote: >>>> >>>>> Hi Vishal, can this be reproduced on a bare metal instance as well? >>>>> Also is this a job or a session cluster? >>>>> >>>>> Thanks >>>>> >>>>> Tim >>>>> >>>>> On Sat, Jun 29, 2019, 7:50 AM Vishal Santoshi < >>>>> vishal.santo...@gmail.com> wrote: >>>>> >>>>>> OK this happened again and it is bizarre ( and is definitely not what >>>>>> I think should happen ) >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> The job failed and I see these logs ( In essence it is keeping the >>>>>> last 5 externalized checkpoints ) but deleting the zk checkpoints >>>>>> directory >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> *06.28.2019 20:33:13.738 2019-06-29 00:33:13,736 INFO >>>>>> org.apache.flink.runtime.checkpoint.CompletedCheckpoint - >>>>>> Checkpoint >>>>>> with ID 5654 at >>>>>> 'xxxxxxxxxx:8020/analytics_eng/kafka-to-hdfs-states/00000000000000000000000000000005/chk-5654' >>>>>> not discarded. 06.28.2019 20:33:13.788 2019-06-29 00:33:13,786 INFO >>>>>> org.apache.flink.runtime.checkpoint.CompletedCheckpoint - >>>>>> Checkpoint >>>>>> with ID 5655 at >>>>>> 'xxxxxxxxxx:8020/analytics_eng/kafka-to-hdfs-states/00000000000000000000000000000005/chk-5655' >>>>>> not discarded. 06.28.2019 20:33:13.838 2019-06-29 00:33:13,836 INFO >>>>>> org.apache.flink.runtime.checkpoint.CompletedCheckpoint - >>>>>> Checkpoint >>>>>> with ID 5656 at >>>>>> 'xxxxxxxxxx8020/analytics_eng/kafka-to-hdfs-states/00000000000000000000000000000005/chk-5656' >>>>>> not discarded. 06.28.2019 20:33:13.888 2019-06-29 00:33:13,886 INFO >>>>>> org.apache.flink.runtime.checkpoint.CompletedCheckpoint - >>>>>> Checkpoint >>>>>> with ID 5657 at >>>>>> 'xxxxxxxxxx:8020/analytics_eng/kafka-to-hdfs-states/00000000000000000000000000000005/chk-5657' >>>>>> not discarded. 06.28.2019 20:33:13.938 2019-06-29 00:33:13,936 INFO >>>>>> org.apache.flink.runtime.checkpoint.CompletedCheckpoint - >>>>>> Checkpoint >>>>>> with ID 5658 at >>>>>> 'xxxxxxxxxx8020/analytics_eng/kafka-to-hdfs-states/00000000000000000000000000000005/chk-5658' >>>>>> not discarded. 06.28.2019 20:33:13.938 2019-06-29 00:33:13,936 INFO >>>>>> org.apache.flink.runtime.zookeeper.ZooKeeperStateHandleStore - Removing >>>>>> /kafka-to-hdfs-v2/kafka-to-hdfs-v2/k8s/checkpoints/00000000000000000000000000000005 >>>>>> from ZooKeeper* >>>>>> >>>>>> The job restarts and this is bizzare. It does not find the ZK >>>>>> checkpoint directory but instead of going to the >>>>>> state.checkpoints.dir to get it's last checkpoint, it restarts from >>>>>> a save point that we started this job with ( resetting the checkpoint id >>>>>> ) >>>>>> like about 15 days ago >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> * 06.28.2019 20:33:20.047 2019-06-29 00:33:20,045 INFO >>>>>> org.apache.flink.runtime.checkpoint.ZooKeeperCompletedCheckpointStore - >>>>>> Recovering checkpoints from ZooKeeper. 06.28.2019 20:33:20.053 >>>>>> 2019-06-29 00:33:20,051 INFO >>>>>> org.apache.flink.runtime.checkpoint.ZooKeeperCompletedCheckpointStore - >>>>>> Trying to fetch 0 checkpoints from storage. 06.28.2019 20:33:20.053 >>>>>> 2019-06-29 00:33:20,051 INFO >>>>>> org.apache.flink.runtime.checkpoint.ZooKeeperCompletedCheckpointStore - >>>>>> Found 0 checkpoints in ZooKeeper. 06.28.2019 20:33:20.054 >>>>>> 2019-06-29 >>>>>> 00:33:20,053 INFO >>>>>> org.apache.flink.runtime.checkpoint.CheckpointCoordinator - Starting >>>>>> job 00000000000000000000000000000005 from savepoint >>>>>> hdfs://nn-crunchy:8020/flink-savepoints_k8s/prod/kafka-to-hdfs/savepoint-000000-128f419cdc6f >>>>>> () 06.28.2019 20:33:20.540 2019-06-29 00:33:20,538 INFO >>>>>> org.apache.flink.runtime.checkpoint.CheckpointCoordinator - Reset >>>>>> the >>>>>> checkpoint ID of job 00000000000000000000000000000005 to 4203. >>>>>> 06.28.2019 20:33:20.540 2019-06-29 00:33:20,538 INFO >>>>>> org.apache.flink.runtime.checkpoint.ZooKeeperCompletedCheckpointStore - >>>>>> Recovering checkpoints from ZooKeeper. 06.28.2019 20:33:20.550 >>>>>> 2019-06-29 00:33:20,549 INFO >>>>>> org.apache.flink.runtime.checkpoint.ZooKeeperCompletedCheckpointStore - >>>>>> Trying to retrieve checkpoint 4202. 06.28.2019 20:33:20.550 >>>>>> 2019-06-29 00:33:20,548 INFO >>>>>> org.apache.flink.runtime.checkpoint.ZooKeeperCompletedCheckpointStore - >>>>>> Found 1 checkpoints in ZooKeeper. 06.28.2019 20:33:20.550 >>>>>> 2019-06-29 >>>>>> 00:33:20,549 INFO >>>>>> org.apache.flink.runtime.checkpoint.ZooKeeperCompletedCheckpointStore - >>>>>> Trying to fetch 1 checkpoints from storage.* >>>>>> >>>>>> >>>>>> >>>>>> This just does not make sense.... >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> >>>>>> On Wed, Jun 5, 2019 at 9:29 AM Vishal Santoshi < >>>>>> vishal.santo...@gmail.com> wrote: >>>>>> >>>>>>> Ok, I will do that. >>>>>>> >>>>>>> On Wed, Jun 5, 2019, 8:25 AM Chesnay Schepler <ches...@apache.org> >>>>>>> wrote: >>>>>>> >>>>>>>> Can you provide us the jobmanager logs? >>>>>>>> >>>>>>>> After the first restart the JM should have started deleting older >>>>>>>> checkpoints as new ones were created. >>>>>>>> After the second restart the JM should have recovered all 10 >>>>>>>> checkpoints, start from the latest, and start pruning old ones as new >>>>>>>> ones >>>>>>>> were created. >>>>>>>> >>>>>>>> So you're running into 2 separate issues here, which is a bit odd. >>>>>>>> >>>>>>>> On 05/06/2019 13:44, Vishal Santoshi wrote: >>>>>>>> >>>>>>>> Any one? >>>>>>>> >>>>>>>> On Tue, Jun 4, 2019, 2:41 PM Vishal Santoshi < >>>>>>>> vishal.santo...@gmail.com> wrote: >>>>>>>> >>>>>>>>> The above is flink 1.8 >>>>>>>>> >>>>>>>>> On Tue, Jun 4, 2019 at 12:32 PM Vishal Santoshi < >>>>>>>>> vishal.santo...@gmail.com> wrote: >>>>>>>>> >>>>>>>>>> I had a sequence of events that created this issue. >>>>>>>>>> >>>>>>>>>> * I started a job and I had the state.checkpoints.num-retained: 5 >>>>>>>>>> >>>>>>>>>> * As expected I have 5 latest checkpoints retained in my hdfs >>>>>>>>>> backend. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> * JM dies ( K8s limit etc ) without cleaning the hdfs directory. >>>>>>>>>> The k8s job restores from the latest checkpoint ( I think ) but as >>>>>>>>>> it >>>>>>>>>> creates new checkpoints it does not delete the older chk point. At >>>>>>>>>> the end >>>>>>>>>> there are now 10 chkpoints, 5 from the old run which remain static >>>>>>>>>> and 5 >>>>>>>>>> latest representing the on going pipe. >>>>>>>>>> >>>>>>>>>> * The JM dies again and restart from the latest from the 5 old >>>>>>>>>> checkpoints. >>>>>>>>>> >>>>>>>>>> This looks a bug in the Job Cluster implementation of flink. It >>>>>>>>>> looks like it is taking the 5th checkpoint from the beginning based >>>>>>>>>> on >>>>>>>>>> num-retained value, Note that it has the same job id and does not >>>>>>>>>> scope to >>>>>>>>>> a new directory. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> https://github.com/apache/flink/blob/1dfdaa417ab7cdca9bef1efe6381c7eb67022aaf/flink-runtime/src/main/java/org/apache/flink/runtime/checkpoint/ZooKeeperCompletedCheckpointStore.java#L109 >>>>>>>>>> >>>>>>>>>> Please tell me if this does not make sense. >>>>>>>>>> >>>>>>>>>> Vishal >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> >>>>>>>>
