Please on committing HDFS-1024 to the hadoop 0.20 branch.

Background:

HDFS-1024 fixes possible trashing of fsimage because of failed copy
from 2NN and NN.  Ordinarily, possible corruption of this proportion
would merit commit w/o need of a vote only Dhruba correctly notes that
UNLESS both NN and 2NN are upgraded, HDFS-1024 becomes an incompatible
change (the NN<->2NN communication will fail always).  IMO, this
incompatible change can be plastered over with a release note; e.g.
WARNING, you MUST update NN and 2NN when you go to 0.20.3 hadoop.  If
you agree with me, please vote +1 on commit.

Thanks,
St.Ack

On Fri, Apr 2, 2010 at 10:38 AM, Stack <[EMAIL PROTECTED]> wrote:

> Please on committing HDFS-1024 to the hadoop 0.20 branch.
>
> Background:
>
> HDFS-1024 fixes possible trashing of fsimage because of failed copy
> from 2NN and NN.  Ordinarily, possible corruption of this proportion
> would merit commit w/o need of a vote only Dhruba correctly notes that
> UNLESS both NN and 2NN are upgraded, HDFS-1024 becomes an incompatible
> change (the NN<->2NN communication will fail always).  IMO, this
> incompatible change can be plastered over with a release note; e.g.
> WARNING, you MUST update NN and 2NN when you go to 0.20.3 hadoop.  If
> you agree with me, please vote +1 on commit.
>

+1. If I recall correctly the NN and 2NN already do a very strict version
check in branch 20, so it's not any more incompatible than any other change.
(I think Dhruba made the version check less strict in the FB branch)

-Todd

--
Todd Lipcon
Software Engineer, Cloudera

+ 1

On 4/2/10, Stack <[EMAIL PROTECTED]> wrote:
> Please on committing HDFS-1024 to the hadoop 0.20 branch.
>
> Background:
>
> HDFS-1024 fixes possible trashing of fsimage because of failed copy
> from 2NN and NN.  Ordinarily, possible corruption of this proportion
> would merit commit w/o need of a vote only Dhruba correctly notes that
> UNLESS both NN and 2NN are upgraded, HDFS-1024 becomes an incompatible
> change (the NN<->2NN communication will fail always).  IMO, this
> incompatible change can be plastered over with a release note; e.g.
> WARNING, you MUST update NN and 2NN when you go to 0.20.3 hadoop.  If
> you agree with me, please vote +1 on commit.
>
> Thanks,
> St.Ack
>

--
Sent from Gmail for mobile | mobile.google.com

Connect to me at http://www.facebook.com/dhruba

+1

J-D

On Fri, Apr 2, 2010 at 10:38 AM, Stack <[EMAIL PROTECTED]> wrote:
> Please on committing HDFS-1024 to the hadoop 0.20 branch.
>
> Background:
>
> HDFS-1024 fixes possible trashing of fsimage because of failed copy
> from 2NN and NN.  Ordinarily, possible corruption of this proportion
> would merit commit w/o need of a vote only Dhruba correctly notes that
> UNLESS both NN and 2NN are upgraded, HDFS-1024 becomes an incompatible
> change (the NN<->2NN communication will fail always).  IMO, this
> incompatible change can be plastered over with a release note; e.g.
> WARNING, you MUST update NN and 2NN when you go to 0.20.3 hadoop.  If
> you agree with me, please vote +1 on commit.
>
> Thanks,
> St.Ack
>

+1

> On 4/2/10, Stack <[EMAIL PROTECTED]>  wrote:
> > Please on committing HDFS-1024 to the hadoop 0.20 branch.
> >
> > Background:
> >
> > HDFS-1024 fixes possible trashing of fsimage because
> > of failed copy from 2NN and NN.  Ordinarily, possible
> > corruption of this proportion would merit commit w/o
> > need of a vote only Dhruba correctly notes that UNLESS
> > both NN and 2NN are upgraded, HDFS-1024 becomes an
> > incompatible change (the NN<->2NN communication will
> > fail always).  IMO, this incompatible change can be
> > plastered over with a release note; e.g.
> > WARNING, you MUST update NN and 2NN when you go to
> > 0.20.3 hadoop.  If you agree with me, please vote +1
> > on commit.

+1 Good catch!

Hairong

On Sat, Apr 3, 2010 at 12:55 PM, Andrew Purtell <[EMAIL PROTECTED]> wrote:

> +1
>
> > On 4/2/10, Stack <[EMAIL PROTECTED]>  wrote:
> > > Please on committing HDFS-1024 to the hadoop 0.20 branch.
> > >
> > > Background:
> > >
> > > HDFS-1024 fixes possible trashing of fsimage because
> > > of failed copy from 2NN and NN.  Ordinarily, possible
> > > corruption of this proportion would merit commit w/o
> > > need of a vote only Dhruba correctly notes that UNLESS
> > > both NN and 2NN are upgraded, HDFS-1024 becomes an
> > > incompatible change (the NN<->2NN communication will
> > > fail always).  IMO, this incompatible change can be
> > > plastered over with a release note; e.g.
> > > WARNING, you MUST update NN and 2NN when you go to
> > > 0.20.3 hadoop.  If you agree with me, please vote +1
> > > on commit.
>
>
>
>
>
>

+1.

Hairong Kuang wrote:
> +1 Good catch!
>
> Hairong
>
> On Sat, Apr 3, 2010 at 12:55 PM, Andrew Purtell <[EMAIL PROTECTED]> wrote:
>
>> +1
>>
>>> On 4/2/10, Stack <[EMAIL PROTECTED]>  wrote:
>>>> Please on committing HDFS-1024 to the hadoop 0.20 branch.
>>>>
>>>> Background:
>>>>
>>>> HDFS-1024 fixes possible trashing of fsimage because
>>>> of failed copy from 2NN and NN.  Ordinarily, possible
>>>> corruption of this proportion would merit commit w/o
>>>> need of a vote only Dhruba correctly notes that UNLESS
>>>> both NN and 2NN are upgraded, HDFS-1024 becomes an
>>>> incompatible change (the NN<->2NN communication will
>>>> fail always).  IMO, this incompatible change can be
>>>> plastered over with a release note; e.g.
>>>> WARNING, you MUST update NN and 2NN when you go to
>>>> 0.20.3 hadoop.  If you agree with me, please vote +1
>>>> on commit.
>>
>>
>>
>>
>>
>

+1

I also thought that version mismatch is FB specific.
Other people will not be able to run different versions of NN and SNN.
--Konstantin

On 4/2/2010 10:41 AM, Todd Lipcon wrote:
> On Fri, Apr 2, 2010 at 10:38 AM, Stack<[EMAIL PROTECTED]>  wrote:
>
>> >  Please on committing HDFS-1024 to the hadoop 0.20 branch.
>> >
>> >  Background:
>> >
>> >  HDFS-1024 fixes possible trashing of fsimage because of failed copy
>> >  from 2NN and NN.  Ordinarily, possible corruption of this proportion
>> >  would merit commit w/o need of a vote only Dhruba correctly notes that
>> >  UNLESS both NN and 2NN are upgraded, HDFS-1024 becomes an incompatible
>> >  change (the NN<->2NN communication will fail always).  IMO, this
>> >  incompatible change can be plastered over with a release note; e.g.
>> >  WARNING, you MUST update NN and 2NN when you go to 0.20.3 hadoop.  If
>> >  you agree with me, please vote +1 on commit.
>> >
> +1. If I recall correctly the NN and 2NN already do a very strict version
> check in branch 20, so it's not any more incompatible than any other change.
> (I think Dhruba made the version check less strict in the FB branch)
>
> -Todd
>
>