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Posted to user@curator.apache.org by Check Peck <co...@gmail.com> on 2014/11/05 18:47:31 UTC
Re: Automatic Restart Zookeeper node
Hi Jordan,
I have one more question on this. As you told me, if zookeeper went down,
then exhibitor will start it but suppose if exhibitor went down, then it
won't get started up right?
So for this case, we need to write a crontab which keeps on checking the
state of exhibitor and restart it if it is down?
On Wed, Oct 1, 2014 at 2:18 PM, Jordan Zimmerman <jordan@jordanzimmerman.com
> wrote:
> Yes
>
>
> On October 1, 2014 at 4:17:00 PM, Check Peck (comptechgeeky@gmail.com)
> wrote:
>
> Thanks Jordan. One last question, as of now it is showing *OFF* next to *Automatic
> Instance Restarts* button so if I turn it ON on the Exhibitor while
> zookeeper is running and taking traffic, then it will be fine? Right?
>
> On Wed, Oct 1, 2014 at 2:11 PM, Jordan Zimmerman <
> jordan@jordanzimmerman.com> wrote:
>
>> Yes, Exhibitor can be used as a co-process to restart down instances.
>> It can also completely manage your ensemble if you like.
>>
>> -JZ
>>
>>
>> On October 1, 2014 at 3:34:10 PM, Check Peck (comptechgeeky@gmail.com)
>> wrote:
>>
>> Checking again to see whether anyone know the answer?
>>
>> On Wed, Sep 24, 2014 at 8:56 AM, Check Peck <co...@gmail.com>
>> wrote:
>>
>>> We have a three node zookeeper cluster and we are also using Exhibitor
>>> on top of each zookeeper node.
>>>
>>> Suppose if any of the zookeeper node goes down or having any errors or
>>> issues then is there any way that it can be restarted?
>>>
>>> I noticed on Exhibitor UI of my zookeeper nodes there is a button for *Automatic
>>> Instance Restarts*
>>>
>>> Does anyone know what does it do? Right now it is in off state.
>>>
>>
>>
>
Re: Automatic Restart Zookeeper node
Posted by Check Peck <co...@gmail.com>.
Thanks Jordan. As of now we have three nodes zookeeper ensemble set up as
below (shown in the exhibitor config panel)
S:1:server1,
S:2:server2,
S:3:server3
And then we have another service which uses above three zookeeper servers
to connect by using curator library so my question is if any one zookeeper
servers went down, then my service which uses zookeeper will be able to
fetch data from any of the znodes from two zookeeper servers or not?
Or do I need all the three zookeeper servers to up then only I will be able
to fetch the data? As I read this line "Three ZooKeeper servers is the
minimum recommended size for an ensemble," on this wiki so got confuse.
https://zookeeper.apache.org/doc/r3.1.2/zookeeperAdmin.html
On Wed, Nov 5, 2014 at 9:49 AM, Jordan Zimmerman <jordan@jordanzimmerman.com
> wrote:
> Yes, that’s true. Someone needs to watch the watcher ;) At Netflix we ran
> Exhibitor in Tomcat and had company wide tools that would watch our Tomcat
> processes.
>
>
> On November 5, 2014 at 12:47:52 PM, Check Peck (comptechgeeky@gmail.com)
> wrote:
>
> Hi Jordan,
>
> I have one more question on this. As you told me, if zookeeper went down,
> then exhibitor will start it but suppose if exhibitor went down, then it
> won't get started up right?
>
> So for this case, we need to write a crontab which keeps on checking the
> state of exhibitor and restart it if it is down?
>
> On Wed, Oct 1, 2014 at 2:18 PM, Jordan Zimmerman <
> jordan@jordanzimmerman.com> wrote:
>
>> Yes
>>
>>
>> On October 1, 2014 at 4:17:00 PM, Check Peck (comptechgeeky@gmail.com)
>> wrote:
>>
>> Thanks Jordan. One last question, as of now it is showing *OFF* next to *Automatic
>> Instance Restarts* button so if I turn it ON on the Exhibitor while
>> zookeeper is running and taking traffic, then it will be fine? Right?
>>
>> On Wed, Oct 1, 2014 at 2:11 PM, Jordan Zimmerman <
>> jordan@jordanzimmerman.com> wrote:
>>
>>> Yes, Exhibitor can be used as a co-process to restart down instances.
>>> It can also completely manage your ensemble if you like.
>>>
>>> -JZ
>>>
>>>
>>> On October 1, 2014 at 3:34:10 PM, Check Peck (comptechgeeky@gmail.com)
>>> wrote:
>>>
>>> Checking again to see whether anyone know the answer?
>>>
>>> On Wed, Sep 24, 2014 at 8:56 AM, Check Peck <co...@gmail.com>
>>> wrote:
>>>
>>>> We have a three node zookeeper cluster and we are also using
>>>> Exhibitor on top of each zookeeper node.
>>>>
>>>> Suppose if any of the zookeeper node goes down or having any errors or
>>>> issues then is there any way that it can be restarted?
>>>>
>>>> I noticed on Exhibitor UI of my zookeeper nodes there is a button for *Automatic
>>>> Instance Restarts*
>>>>
>>>> Does anyone know what does it do? Right now it is in off state.
>>>>
>>>
>>>
>>
>
Re: Automatic Restart Zookeeper node
Posted by Owen Kim <oh...@gmail.com>.
As an alternative approach, I run monit on our zookeeper machines to
periodically check "stat" and restart zookeeper if it reports errors a
certain number of times.
On Wed, Nov 5, 2014 at 9:49 AM, Jordan Zimmerman <jordan@jordanzimmerman.com
> wrote:
> Yes, that’s true. Someone needs to watch the watcher ;) At Netflix we ran
> Exhibitor in Tomcat and had company wide tools that would watch our Tomcat
> processes.
>
>
> On November 5, 2014 at 12:47:52 PM, Check Peck (comptechgeeky@gmail.com)
> wrote:
>
> Hi Jordan,
>
> I have one more question on this. As you told me, if zookeeper went down,
> then exhibitor will start it but suppose if exhibitor went down, then it
> won't get started up right?
>
> So for this case, we need to write a crontab which keeps on checking the
> state of exhibitor and restart it if it is down?
>
> On Wed, Oct 1, 2014 at 2:18 PM, Jordan Zimmerman <
> jordan@jordanzimmerman.com> wrote:
>
>> Yes
>>
>>
>> On October 1, 2014 at 4:17:00 PM, Check Peck (comptechgeeky@gmail.com)
>> wrote:
>>
>> Thanks Jordan. One last question, as of now it is showing *OFF* next to *Automatic
>> Instance Restarts* button so if I turn it ON on the Exhibitor while
>> zookeeper is running and taking traffic, then it will be fine? Right?
>>
>> On Wed, Oct 1, 2014 at 2:11 PM, Jordan Zimmerman <
>> jordan@jordanzimmerman.com> wrote:
>>
>>> Yes, Exhibitor can be used as a co-process to restart down instances.
>>> It can also completely manage your ensemble if you like.
>>>
>>> -JZ
>>>
>>>
>>> On October 1, 2014 at 3:34:10 PM, Check Peck (comptechgeeky@gmail.com)
>>> wrote:
>>>
>>> Checking again to see whether anyone know the answer?
>>>
>>> On Wed, Sep 24, 2014 at 8:56 AM, Check Peck <co...@gmail.com>
>>> wrote:
>>>
>>>> We have a three node zookeeper cluster and we are also using
>>>> Exhibitor on top of each zookeeper node.
>>>>
>>>> Suppose if any of the zookeeper node goes down or having any errors or
>>>> issues then is there any way that it can be restarted?
>>>>
>>>> I noticed on Exhibitor UI of my zookeeper nodes there is a button for *Automatic
>>>> Instance Restarts*
>>>>
>>>> Does anyone know what does it do? Right now it is in off state.
>>>>
>>>
>>>
>>
>
Re: Automatic Restart Zookeeper node
Posted by Jordan Zimmerman <jo...@jordanzimmerman.com>.
Yes, that’s true. Someone needs to watch the watcher ;) At Netflix we ran Exhibitor in Tomcat and had company wide tools that would watch our Tomcat processes.
On November 5, 2014 at 12:47:52 PM, Check Peck (comptechgeeky@gmail.com) wrote:
Hi Jordan,
I have one more question on this. As you told me, if zookeeper went down, then exhibitor will start it but suppose if exhibitor went down, then it won't get started up right?
So for this case, we need to write a crontab which keeps on checking the state of exhibitor and restart it if it is down?
On Wed, Oct 1, 2014 at 2:18 PM, Jordan Zimmerman <jo...@jordanzimmerman.com> wrote:
Yes
On October 1, 2014 at 4:17:00 PM, Check Peck (comptechgeeky@gmail.com) wrote:
Thanks Jordan. One last question, as of now it is showing OFF next to Automatic Instance Restarts button so if I turn it ON on the Exhibitor while zookeeper is running and taking traffic, then it will be fine? Right?
On Wed, Oct 1, 2014 at 2:11 PM, Jordan Zimmerman <jo...@jordanzimmerman.com> wrote:
Yes, Exhibitor can be used as a co-process to restart down instances. It can also completely manage your ensemble if you like.
-JZ
On October 1, 2014 at 3:34:10 PM, Check Peck (comptechgeeky@gmail.com) wrote:
Checking again to see whether anyone know the answer?
On Wed, Sep 24, 2014 at 8:56 AM, Check Peck <co...@gmail.com> wrote:
We have a three node zookeeper cluster and we are also using Exhibitor on top of each zookeeper node.
Suppose if any of the zookeeper node goes down or having any errors or issues then is there any way that it can be restarted?
I noticed on Exhibitor UI of my zookeeper nodes there is a button for Automatic Instance Restarts
Does anyone know what does it do? Right now it is in off state.