Wilfred Spiegelenburg commented on YARN-2578:

To address [~vinodkv] comments: The active RM is completely shut off from the 
network so are all the other services on the node, including zookeeper. The RM 
can update zookeeper but that will never be propagated outside of the node to 
the other zookeeper nodes. It can thus not be seen by the standby RM. The 
standby RM detects no updates in zookeeper for the timeout period and becomes 
the active node. That is the normal HA behaviour from the standby node as if 
the RM would have crashed.

> NM does not failover timely if RM node network connection fails
> ---------------------------------------------------------------
>                 Key: YARN-2578
>                 URL: https://issues.apache.org/jira/browse/YARN-2578
>             Project: Hadoop YARN
>          Issue Type: Bug
>          Components: nodemanager
>    Affects Versions: 2.5.1
>            Reporter: Wilfred Spiegelenburg
>         Attachments: YARN-2578.patch
> The NM does not fail over correctly when the network cable of the RM is 
> unplugged or the failure is simulated by a "service network stop" or a 
> firewall that drops all traffic on the node. The RM fails over to the standby 
> node when the failure is detected as expected. The NM should than re-register 
> with the new active RM. This re-register takes a long time (15 minutes or 
> more). Until then the cluster has no nodes for processing and applications 
> are stuck.
> Reproduction test case which can be used in any environment:
> - create a cluster with 3 nodes
>     node 1: ZK, NN, JN, ZKFC, DN, RM, NM
>     node 2: ZK, NN, JN, ZKFC, DN, RM, NM
>     node 3: ZK, JN, DN, NM
> - start all services make sure they are in good health
> - kill the network connection of the RM that is active using one of the 
> network kills from above
> - observe the NN and RM failover
> - the DN's fail over to the new active NN
> - the NM does not recover for a long time
> - the logs show a long delay and traces show no change at all
> The stack traces of the NM all show the same set of threads. The main thread 
> which should be used in the re-register is the "Node Status Updater" This 
> thread is stuck in:
> {code}
> "Node Status Updater" prio=10 tid=0x00007f5a6cc99800 nid=0x18d0 in 
> Object.wait() [0x00007f5a51fc1000]
>    java.lang.Thread.State: WAITING (on object monitor)
>       at java.lang.Object.wait(Native Method)
>       - waiting on <0x00000000ed62f488> (a org.apache.hadoop.ipc.Client$Call)
>       at java.lang.Object.wait(Object.java:503)
>       at org.apache.hadoop.ipc.Client.call(Client.java:1395)
>       - locked <0x00000000ed62f488> (a org.apache.hadoop.ipc.Client$Call)
>       at org.apache.hadoop.ipc.Client.call(Client.java:1362)
>       at 
> org.apache.hadoop.ipc.ProtobufRpcEngine$Invoker.invoke(ProtobufRpcEngine.java:206)
>       at com.sun.proxy.$Proxy26.nodeHeartbeat(Unknown Source)
>       at 
> org.apache.hadoop.yarn.server.api.impl.pb.client.ResourceTrackerPBClientImpl.nodeHeartbeat(ResourceTrackerPBClientImpl.java:80)
> {code}
> The client connection which goes through the proxy can be traced back to the 
> ResourceTrackerPBClientImpl. The generated proxy does not time out and we 
> should be using a version which takes the RPC timeout (from the 
> configuration) as a parameter.

This message was sent by Atlassian JIRA

Reply via email to