migrating solr 4.2.1 to 5.X

[Midas A <te...@gmail.com>]

I want migrate from solr 4.2.1 to 5.X version hten my question is

- can i use same snapshot of 4.2.1 in 5.x.x

Actually Indexing will take long time in my case then it would be possible
to do
or we should not do this.


next similar question is

- can we replicate 4.2.1 master to slave 5.x.x solr

Re: migrating solr 4.2.1 to 5.X

[Erick Erickson <er...@gmail.com>]

Well, a Solr index is just a bunch of files. So what I'd do is grab two
machines that are lying around (or even just one with two Solrs)
and try it.

You could just copy the whole Solr tree from your master to machine 1,
from your slave to machine 2. You'd have to change solrconfig on machine 2
to point to machine1, but otherwise that's pretty much it.

Now you can freely try it without endangering your production system.

If the indexes are too big, just set up your test machines and index a few (say
10,000 docs) to each _then_ try the upgrade.

Yeah, upgrading is always "interesting", I shudder every time  I have to...

Best,
Erick

On Wed, Jan 27, 2016 at 5:54 AM, Shawn Heisey <ap...@elyograg.org> wrote:
> On 1/27/2016 2:00 AM, Zaccheo Bagnati wrote:
>> I apologize for connecting to this thread but I'm interested in this topic
>> as well. I think we have a similar configuration: solr 4.8, standard
>> master/slave replication, data is indexed on master and then replicated to
>> slave. I'm investigating how to migrate to solr 5.*.
>> Erick, you say that there is a full backward compatibility between 4.* and
>> 5.* so, for example, we could migrate the slave (and it will continue to
>> read old indexes), then migrate the master (and it could could even update
>> old indexes without need for full reindex). It seems too simple... and I
>> hope it will be so, but my experience of migrations is not so painless as
>> you say...(I'm not referring to SOLR)
>> Is there anyone who tried this approach on a production environment? What I
>> should be more careful of? Is there any incompatibility in REST calls and
>> responses?
>
> Upgrading slaves first and then the master is the recommended way to do
> upgrades in a master/slave installation.  Many people have done upgrades
> in this exact way with success.
>
> I personally would completely rebuild the index once I had the masters
> upgraded, so Solr will perform best.
>
> Thanks,
> Shawn
>

Re: migrating solr 4.2.1 to 5.X

[Shawn Heisey <ap...@elyograg.org>]

On 1/27/2016 2:00 AM, Zaccheo Bagnati wrote:
> I apologize for connecting to this thread but I'm interested in this topic
> as well. I think we have a similar configuration: solr 4.8, standard
> master/slave replication, data is indexed on master and then replicated to
> slave. I'm investigating how to migrate to solr 5.*.
> Erick, you say that there is a full backward compatibility between 4.* and
> 5.* so, for example, we could migrate the slave (and it will continue to
> read old indexes), then migrate the master (and it could could even update
> old indexes without need for full reindex). It seems too simple... and I
> hope it will be so, but my experience of migrations is not so painless as
> you say...(I'm not referring to SOLR)
> Is there anyone who tried this approach on a production environment? What I
> should be more careful of? Is there any incompatibility in REST calls and
> responses?

Upgrading slaves first and then the master is the recommended way to do
upgrades in a master/slave installation.  Many people have done upgrades
in this exact way with success.

I personally would completely rebuild the index once I had the masters
upgraded, so Solr will perform best.

Thanks,
Shawn

Re: migrating solr 4.2.1 to 5.X

[Zaccheo Bagnati <za...@gmail.com>]

Hi,
I apologize for connecting to this thread but I'm interested in this topic
as well. I think we have a similar configuration: solr 4.8, standard
master/slave replication, data is indexed on master and then replicated to
slave. I'm investigating how to migrate to solr 5.*.
Erick, you say that there is a full backward compatibility between 4.* and
5.* so, for example, we could migrate the slave (and it will continue to
read old indexes), then migrate the master (and it could could even update
old indexes without need for full reindex). It seems too simple... and I
hope it will be so, but my experience of migrations is not so painless as
you say...(I'm not referring to SOLR)
Is there anyone who tried this approach on a production environment? What I
should be more careful of? Is there any incompatibility in REST calls and
responses?
Thank you

Il giorno mar 26 gen 2016 alle ore 18:31 Erick Erickson <
erickerickson@gmail.com> ha scritto:

> Yes and Yes. The developers try very hard to make Solr
> one major release backwards compatible. So 5x should be
> able to read 4x just fine.
>
> Nothing has really changed in replication, so 5x supports
> master/slave. It's just becoming less popular as SolrCloud
> is significantly easier to operationalize.
>
> Note that as segments get written they will be transformed from 4x
> format to 5x. And you can also use the index upgrade tool here:
>
> https://lucene.apache.org/core/5_0_0/core/org/apache/lucene/index/IndexUpgrader.html
>
> to transform your 4x to 5x
>
> Best,
> Erick
>
> On Tue, Jan 26, 2016 at 7:51 AM, Midas A <te...@gmail.com> wrote:
> > I want migrate from solr 4.2.1 to 5.X version hten my question is
> >
> > - can i use same snapshot of 4.2.1 in 5.x.x
> >
> > Actually Indexing will take long time in my case then it would be
> possible
> > to do
> > or we should not do this.
> >
> >
> > next similar question is
> >
> > - can we replicate 4.2.1 master to slave 5.x.x solr
>

Re: migrating solr 4.2.1 to 5.X

[Erick Erickson <er...@gmail.com>]

Yes and Yes. The developers try very hard to make Solr
one major release backwards compatible. So 5x should be
able to read 4x just fine.

Nothing has really changed in replication, so 5x supports
master/slave. It's just becoming less popular as SolrCloud
is significantly easier to operationalize.

Note that as segments get written they will be transformed from 4x
format to 5x. And you can also use the index upgrade tool here:
https://lucene.apache.org/core/5_0_0/core/org/apache/lucene/index/IndexUpgrader.html

to transform your 4x to 5x

Best,
Erick

On Tue, Jan 26, 2016 at 7:51 AM, Midas A <te...@gmail.com> wrote:
> I want migrate from solr 4.2.1 to 5.X version hten my question is
>
> - can i use same snapshot of 4.2.1 in 5.x.x
>
> Actually Indexing will take long time in my case then it would be possible
> to do
> or we should not do this.
>
>
> next similar question is
>
> - can we replicate 4.2.1 master to slave 5.x.x solr