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https://issues.apache.org/jira/browse/ZOOKEEPER-3920?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17187080#comment-17187080
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Andre Price commented on ZOOKEEPER-3920:
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[~daominah] - Are you using docker? – If so that configuration will only work 
will only work if the IP addresses being used are assigned to the container. In 
the example I had above the container host names were used which resolved to 
the container IP so the bind worked. But the network being used was just a 
bridge network so the cluster only really works locally. If the 192.168.99.10x 
addresses you are using are the addresses for the host machine then you will 
need to run the docker container using the host network driver (i.e. run with 
_--network=host_) for the bind to succeed. 

I think part of the fix for this should probably address the ability to run 
zookeeper in containers using a bridge network driver and allow binding to 
0.0.0.0 even if the server address in the config (used by other servers/quorum) 
has a different IP. That is indirectly addressed in my hacky commit above but 
I'm not sure it will cover all cases or doesn't cause more subtle issues :).

> Zookeeper clients timeout after leader change
> ---------------------------------------------
>
>                 Key: ZOOKEEPER-3920
>                 URL: https://issues.apache.org/jira/browse/ZOOKEEPER-3920
>             Project: ZooKeeper
>          Issue Type: Bug
>          Components: quorum, server
>    Affects Versions: 3.6.1
>            Reporter: Andre Price
>            Priority: Major
>         Attachments: stack.yml, zk_repro.zip
>
>
> [Sorry I believe this is a dupe of 
> https://issues.apache.org/jira/browse/ZOOKEEPER-3828 and potentially 
> https://issues.apache.org/jira/browse/ZOOKEEPER-3466 
> But i am not able to attach files there for some reason so creating a new 
> issue which hopefully allows me]
> We are encountering an issue where failing over from the leader results in 
> zookeeper clients not being able to connect successfully. They timeout 
> waiting for a response from the server. We are attempting to upgrade some 
> existing zookeeper clusters from 3.4.14 to 3.6.1 (not sure if relevant but 
> stating incase it helps with pinpointing issue) which is effectively blocked 
> by this issue. We perform the rolling upgrade (followers first then leader 
> last) and it seems to go successfully by all indicators. But we end up in the 
> state described in this issue where if the leader changes (either due to 
> restart or stopping) the cluster does not seem able to start new sessions.
> I've gathered some TRACE logs from our servers and will attach in the hopes 
> they can help figure this out. 
> Attached zk_repro.zip which contains the following:
>  * zoo.cfg used in one of the instances (they are all the same except for the 
> local server's ip being 0.0.0.0 in each)
>  * zoo.cfg.dynamic.next (don't think this is used anywhere but is written by 
> zookeeper at some point - I think when the first 3.6.1 container becomes 
> leader based on the value – the file is in all containers and is the same in 
> all as well)
>  * s\{1,2,3}_zk.log - logs from each of the 3 servers. Estimated time of 
> repro start indicated by "// REPRO START" text and whitespace in logs
>  * repro_steps.txt - rough steps executed that result in the server logs 
> attached
>  
> I'll summarize the repro here also:
>  # Initially it appears to be a healthy 3 node ensemble all running 3.6.1. 
> Server ids are 1,2,3 and 3 is the leader. Dynamic config/reconfiguration is 
> disabled.
>  # invoke srvr on each node (to verify setup and also create bookmark in logs)
>  # Do a zkCli get of /zookeeper/quota  which succeeds
>  # Do a restart of the leader (to same image/config) (server 2 now becomes 
> leader, 3 is back as follower)
>  # Try to perform the same zkCli get which times out (this get is done within 
> the container)
>  # Try to perform the same zkCli get but from another machine, this also 
> times out
>  # Invoke srvr on each node again (to verify that 2 is now the 
> leader/bookmark)
>  # Do a restart of server 2 (3 becomes leader, 2 follower)
>  # Do a zkCli get of /zookeeper/quota which succeeds
>  # Invoke srvr on each node again (to verify that 3 is leader)
> I tried to keep the other ZK traffic to a minimum but there are likely some 
> periodic mntr requests mixed from our metrics scraper.



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