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Zookeeper >> mail # user >> Healthcheck using the stat command


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Re: Healthcheck using the stat command
If the node is "leader", "follower" or "observer" you are ok. That's all
you should need to look for. ruok just checks to see if the port is
responding and the code is running, pretty much. stat will actually look at
the system and see if the zkserver has started. If so, you'll get some
info, if not, you'll see
"This ZooKeeper instance is not currently serving requests"

C

On Mon, Jan 23, 2012 at 11:24 PM, Jonathan Simms <[EMAIL PROTECTED]> wrote:

> On Mon, Jan 23, 2012 at 5:16 PM, Jordan Zimmerman
> <[EMAIL PROTECTED]> wrote:
> > The problem with 'ruok' is that it doesn't tell you the state of the
> > Instance. 'ruok' might return 'imok' but the instance might not be
> serving
> > due to some other error. Only a 'stat' will tell you that.
> >
> > -JZ
> >
>
> Can you provide an example of what that would look like? A high
> Outstanding count? A Mode that's not "leader", "follower", or
> "observer"?
>
> -J
>
>
> > On 1/23/12 1:51 PM, "Philip Smith" <[EMAIL PROTECTED]> wrote:
> >
> >>There is a batch java program that does a health check:
> >>
> >>validateZookeeperService.validateZookeeperService()
> >>
> >>
> >>which basically runs the ruok command. You could run the stat command and
> >>parse out the response but I think 99% of what you want could be simply
> >>looking for 'imok' in the response to the ruok command.
> >>
> >>philip_smith@st11p00td-devlog001:~ 2 $ alias zkok
> >>alias zkok='for idx in 1 2 3 4 5 ; do export
> >>zkserver="st11p00td-zookeeper00${idx}" ; echo "$zkserver $( echo ruok |
> >>nc  $zkserver 2181 )" ; done'
> >>philip_smith@st11p00td-devlog001:~ 3 $ zkok
> >>st11p00td-zookeeper001 imok
> >>st11p00td-zookeeper002 imok
> >>st11p00td-zookeeper003 imok
> >>st11p00td-zookeeper004 imok
> >>st11p00td-zookeeper005 imok
> >>philip_smith@st11p00td-devlog001:~ 4 $
> >>
> >>
> >>On Jan 23, 2012, at 1:45 PM, Natarajan Suresh wrote:
> >>
> >>> I am trying to write a small health check script for the zookeeper
> >>>instances. The "stat" command gives me an output like this:
> >>> ===========================Zookeeper version: 3.3.3-1073969, built on
> >>>02/23/2011 22:27 GMTClients:
> >>>/127.0.0.1:38929[0](queued=0,recved=1,sent=0)
> >>>/17.155.7.152:37603[1](queued=0,recved=474752,sent=474752)
> >>> Latency min/avg/max: 0/0/35Received: 1113675Sent: 1113706Outstanding:
> >>>0Zxid: 0x2000e2925Mode: followerNode count:
> 71==========================> >>> How do I know that the server is ok ? I do not have a bad instance with
> >>>me to checkout what the output will be in that case.
> >>> If anyone has already written a health check script, can you please
> >>>share with me ?
> >>> Thanks
> >>> |Suresh|
> >>
> >>
> >>Regards, Philip
> >>
> >>Philip Smith
> >>Senior Software Engineer
> >>[EMAIL PROTECTED]
> >>408 862-1360 office
> >>530 574-1659 mobile
> >>
> >
>