Re: Cannot stop Kafka server if zookeeper is shutdown first

Since we have heard back from Stefan on this issue, we should just ask him to release another version of ZkClient with the fixes we want. It may be better to take the discussion of whether or not we should replace ZkClient with Curator to its own KIP thread. In general, there are several issues we

Re: Cannot stop Kafka server if zookeeper is shutdown first

Hi, I don't have enough context to know if replacing ZkClient is important right now. However, I did take a look at the code to see how extensively ZkClient gets used and I agree with Gwen that replacing it is a bigger task and will need further testing too, to ensure they don't have issues o

Re: Cannot stop Kafka server if zookeeper is shutdown first

Hi, KAFKA-1155 is likely Zookeeper and not the specific client. I believe the rest are already fixed in ZKClient and its a matter of asking them to release, rebase our code and make sure the issues are resolved (or that we use the features ZKClient added to resolve them). I'm a fan of Curator, bu

Re: Cannot stop Kafka server if zookeeper is shutdown first

<< A more abstract interface to the distributed coordination service that could be configured to use alternatives like consul or etcd would be very useful imho. +1 If we make the curator changes lets take the time to first build an interface please we can expose both meta data and async notificat

Re: Cannot stop Kafka server if zookeeper is shutdown first

While on the subject of zkclient, also consider KAFKA-1793. A more abstract interface to the distributed coordination service that could be configured to use alternatives like consul or etcd would be very useful imho. Dana FWIW - the ZkClient project team have merged the pull request that I had s

Re: Cannot stop Kafka server if zookeeper is shutdown first

curator handles sasl connection https://issues.apache.org/jira/browse/KAFKA-1695 On Wed, Feb 4, 2015, at 06:10 AM, Jaikiran Pai wrote: > FWIW - the ZkClient project team have merged the pull request that I had > submitted to allow for timeouts to operations > https://github.com/sgroschupf/zkclie

Re: Cannot stop Kafka server if zookeeper is shutdown first

FWIW - the ZkClient project team have merged the pull request that I had submitted to allow for timeouts to operations https://github.com/sgroschupf/zkclient/pull/29. I heard from Johannes (from the ZkClient project team) that they don't have any specific release date in mind but are willing to

Re: Cannot stop Kafka server if zookeeper is shutdown first

Now may be a good time. We could verify if Curator has fixed the known issues we have seen so far, an incomplete list would be: KAFKA-1082 KAFKA-1155 KAFKA-1907

Re: Cannot stop Kafka server if zookeeper is shutdown first

+1 on using curator. On Tue, Feb 3, 2015 at 10:09 PM, Manikumar Reddy wrote: > I think we should consider to moving to apache curator (KAFKA-873). > Curator is now more mature and a apache top-level project. > > > On Wed, Feb 4, 2015 at 11:29 AM, Harsha wrote: > > > Any reason not to go with a

Re: Cannot stop Kafka server if zookeeper is shutdown first

I think we should consider to moving to apache curator (KAFKA-873). Curator is now more mature and a apache top-level project. On Wed, Feb 4, 2015 at 11:29 AM, Harsha wrote: > Any reason not to go with apache curator http://curator.apache.org/ . > -Harsha > On Tue, Feb 3, 2015, at 09:55 PM, Gu

Re: Cannot stop Kafka server if zookeeper is shutdown first

Any reason not to go with apache curator http://curator.apache.org/ . -Harsha On Tue, Feb 3, 2015, at 09:55 PM, Guozhang Wang wrote: > I am also +1 on Neha's suggestion that "At some point, if we find > ourselves > fiddling too much with ZkClient, it wouldn't hurt to write our own little > zookeepe

Re: Cannot stop Kafka server if zookeeper is shutdown first

I am also +1 on Neha's suggestion that "At some point, if we find ourselves fiddling too much with ZkClient, it wouldn't hurt to write our own little zookeeper client wrapper." since we have accumulated a bunch of issues with zkClient which takes long time be resolved if ever, so we ended up have s

Re: Cannot stop Kafka server if zookeeper is shutdown first

Yes, that's the plan :) -Jaikiran On Wednesday 04 February 2015 12:33 AM, Gwen Shapira wrote: So I think the current plan is: 1. Add timeout in zkclient 2. Ask zkclient to release new version (we need it for few other things too) 3. Rebase on new zkclient 4. Fix this jira and the few others than

Re: Cannot stop Kafka server if zookeeper is shutdown first

So I think the current plan is: 1. Add timeout in zkclient 2. Ask zkclient to release new version (we need it for few other things too) 3. Rebase on new zkclient 4. Fix this jira and the few others than were waiting for the new zkclient Does that make sense? Gwen On Mon, Feb 2, 2015 at 8:33 PM,

Re: Cannot stop Kafka server if zookeeper is shutdown first

I just heard back from Stefan, who manages the ZkClient repo and he seems to be open to have these changes be part of ZkClient project. I'll be creating a pull request for that project to have it reviewed and merged. Although I haven't heard of exact release plans, Stefan's reply did indicate t

Re: Cannot stop Kafka server if zookeeper is shutdown first

Thanks for pointing to that repo! I just had a look at it and it appears that the project isn't much active (going by the lack of activity). The latest contribution is from Gwen and that was around 3 months back. I haven't found release plans for that project or a place to ask about it (filing

Re: Cannot stop Kafka server if zookeeper is shutdown first

I did! Thanks for clarifying :) The client that is part of Zookeeper itself actually does support timeouts. On Mon, Feb 2, 2015 at 9:54 AM, Guozhang Wang wrote: > Hi Jaikiran, > > I think Gwen was talking about contributing to ZkClient project: > > https://github.com/sgroschupf/zkclient > > Guo

Re: Cannot stop Kafka server if zookeeper is shutdown first

Hi Jaikiran, I think Gwen was talking about contributing to ZkClient project: https://github.com/sgroschupf/zkclient Guozhang On Sun, Feb 1, 2015 at 5:30 AM, Jaikiran Pai wrote: > Hi Gwen, > > Yes, the KafkaZkClient is a wrapper around ZkClient and not a complete > replacement. > > As for co

Re: Cannot stop Kafka server if zookeeper is shutdown first

Hi Gwen, Yes, the KafkaZkClient is a wrapper around ZkClient and not a complete replacement. As for contributing to Zookeeper, yes that indeed in on my mind, but I haven't yet had a chance to really look deeper into Zookeeper or get in touch with their dev team to try and explain this potent

Re: Cannot stop Kafka server if zookeeper is shutdown first

It looks like the new KafkaZkClient is a wrapper around ZkClient, but not a replacement. Did I get it right? I think a wrapper for ZkClient can be useful - for example KAFKA-1664 can also use one. However, I'm wondering why not contribute the fix directly to ZKClient project and ask for a release

Re: Cannot stop Kafka server if zookeeper is shutdown first

Neha, Ewen (and others), my initial attempt to solve this is uploaded here https://reviews.apache.org/r/30477/. It solves the shutdown problem and now the server shuts down even when Zookeeper has gone down before the Kafka server. I went with the approach of introducing a custom (enhanced) Zk

Re: Cannot stop Kafka server if zookeeper is shutdown first

Ewen is right. ZkClient APIs are blocking and the right fix for this seems to be patching ZkClient. At some point, if we find ourselves fiddling too much with ZkClient, it wouldn't hurt to write our own little zookeeper client wrapper. On Thu, Jan 29, 2015 at 12:57 AM, Ewen Cheslack-Postava wrote

Re: Cannot stop Kafka server if zookeeper is shutdown first

Looks like a bug to me -- the underlying ZK library wraps a lot of blocking method implementations with waitUntilConnected() calls without any timeouts. Ideally we could just add a version of ZkUtils.getController() with a timeout, but I don't see an easy way to accomplish that with ZkClient. Ther

Re: Cannot stop Kafka server if zookeeper is shutdown first

The main culprit is this thread which goes into "forever retry connection to a closed zookeeper" when I shutdown Kafka (via a Ctrl + C) after zookeeper has already been shutdown. I have attached the complete thread dump, but I don't know if it will be delivered to the mailing list. "Thread-2"

Re: Cannot stop Kafka server if zookeeper is shutdown first

For a clean shutdown, the broker tries to talk to the controller and also issues reads to zookeeper. Possibly that is where it tries to reconnect to zk. It will help to look at the thread dump. Thanks Neha On Fri, Jan 23, 2015 at 8:53 PM, Jaikiran Pai wrote: > I was just playing around with the

Cannot stop Kafka server if zookeeper is shutdown first

I was just playing around with the RC2 of 0.8.2 and noticed that if I shutdown zookeeper first I can't shutdown Kafka server at all since it goes into a never ending attempt to reconnect with zookeeper. I had to kill the Kafka process to stop it. I tried it against trunk too and there too I see