Unloading and loading a Collection in SolrCloud with external Zookeeper ensemble

Previous Topic Next Topic
 
classic Classic list List threaded Threaded
6 messages Options
Reply | Threaded
Open this post in threaded view
|

Unloading and loading a Collection in SolrCloud with external Zookeeper ensemble

Gajanan
I have unloaded all cores of a collection in SolrCloud (8.x.x ) using
coreAdmin APIs as UNLOAD collection is not available in collections API. Now
I want reload the unloaded collection using APIs only.
When trying with coreAdmin APIs I am getting "Non legacy mode CoreNodeName
not found."
When trying with collections APIs it is reloaded but shows no cores
available.




--
Sent from: https://lucene.472066.n3.nabble.com/Solr-User-f472068.html
Reply | Threaded
Open this post in threaded view
|

Re: Unloading and loading a Collection in SolrCloud with external Zookeeper ensemble

Erick Erickson
As stated in the docs, using the core admin API when using SolrCloud is not recommended,
for just reasons like this. While SolrCloud _does_ use the Core Admin API, it’s usage
has to be very precise.

You apparently didn’t heed this warning in the UNLOAD command for the collections API:

"Unloading all cores in a SolrCloud collection causes the removal of that collection’s metadata from ZooKeeper.”

This latter is what the “non legacy mode…” message is about. In earlier versions of Solr,
the ZK information was recreated when Solr found a core.properties file, but that had
its own problems so was removed.

Your best bet now is to wipe your directories, create a new collection and re-index.

If you absolutely can’t reindex:
0> save away one index directory from every shard, it doesn’t matter which.
1> create the collection, with the exact same number of shards and a replicationFactor of 1
2> shut down all the Solr instances
3> copy the index directory from <0> to ’the right place”. For instance, if you
    have a collection blah, you’ll have some directory like blah_shard1_replica_n1/data/index.
    It’s critical that you replace the contents of data/index with the contents of the
    directory saved in <0> from the _same_ shard, shard1 in this example.
4> start your Solr instances back up
5> use ADDREPLICA to build out the collection to have as many replicas as you need.

Good luck!
Erick


> On Nov 12, 2020, at 6:32 AM, Gajanan <[hidden email]> wrote:
>
> I have unloaded all cores of a collection in SolrCloud (8.x.x ) using
> coreAdmin APIs as UNLOAD collection is not available in collections API. Now
> I want reload the unloaded collection using APIs only.
> When trying with coreAdmin APIs I am getting "Non legacy mode CoreNodeName
> not found."
> When trying with collections APIs it is reloaded but shows no cores
> available.
>
>
>
>
> --
> Sent from: https://lucene.472066.n3.nabble.com/Solr-User-f472068.html

Reply | Threaded
Open this post in threaded view
|

Re: Unloading and loading a Collection in SolrCloud with external Zookeeper ensemble

Gajanan
Hi Erick, thanks for the reply.
I am working on a application where a  solr collection is being created per
usage of application accumulating lot of them over period of time . In order
to keep memory requirements under control, I am unloading collections not in
current usage and loading them whenever required.
This was working in non cloud mode with coreAdmin APIs. Now because of
scaling requirements we want to shift to SolrCloud mode. we want to continue
with same application design. can you suggest, how to implement a similar
solution in SolrCloud context.

-Gajanan



--
Sent from: https://lucene.472066.n3.nabble.com/Solr-User-f472068.html
Reply | Threaded
Open this post in threaded view
|

Re: Unloading and loading a Collection in SolrCloud with external Zookeeper ensemble

Erick Erickson
I don’t really have any good alternatives. There’s an open JIRA for
this, see: SOLR-6399

This would be a pretty big chunk of work, which is one of the reasons
this JIRA has languished…

Sorry I can’t be more helpful,
Erick

> On Nov 15, 2020, at 11:00 AM, Gajanan <[hidden email]> wrote:
>
> Hi Erick, thanks for the reply.
> I am working on a application where a  solr collection is being created per
> usage of application accumulating lot of them over period of time . In order
> to keep memory requirements under control, I am unloading collections not in
> current usage and loading them whenever required.
> This was working in non cloud mode with coreAdmin APIs. Now because of
> scaling requirements we want to shift to SolrCloud mode. we want to continue
> with same application design. can you suggest, how to implement a similar
> solution in SolrCloud context.
>
> -Gajanan
>
>
>
> --
> Sent from: https://lucene.472066.n3.nabble.com/Solr-User-f472068.html

Reply | Threaded
Open this post in threaded view
|

Re: Unloading and loading a Collection in SolrCloud with external Zookeeper ensemble

Ilan Ginzburg
An unelegant alternative is to back up and delete a collection in lieu of
unload, restore it in lieu of load...

Ilan

On Sun, Nov 15, 2020 at 6:56 PM Erick Erickson <[hidden email]>
wrote:

> I don’t really have any good alternatives. There’s an open JIRA for
> this, see: SOLR-6399
>
> This would be a pretty big chunk of work, which is one of the reasons
> this JIRA has languished…
>
> Sorry I can’t be more helpful,
> Erick
>
> > On Nov 15, 2020, at 11:00 AM, Gajanan <[hidden email]> wrote:
> >
> > Hi Erick, thanks for the reply.
> > I am working on a application where a  solr collection is being created
> per
> > usage of application accumulating lot of them over period of time . In
> order
> > to keep memory requirements under control, I am unloading collections
> not in
> > current usage and loading them whenever required.
> > This was working in non cloud mode with coreAdmin APIs. Now because of
> > scaling requirements we want to shift to SolrCloud mode. we want to
> continue
> > with same application design. can you suggest, how to implement a similar
> > solution in SolrCloud context.
> >
> > -Gajanan
> >
> >
> >
> > --
> > Sent from: https://lucene.472066.n3.nabble.com/Solr-User-f472068.html
>
>
Reply | Threaded
Open this post in threaded view
|

Re: Unloading and loading a Collection in SolrCloud with external Zookeeper ensemble

Gajanan
Thanks for the replies. Wanted to make sure that I am not missing on
something already available. Now that everything is clear, I may have to go
for application re-design or choose an approach, not so elegant, as
suggested.
Thanks all.
-Gajanan



--
Sent from: https://lucene.472066.n3.nabble.com/Solr-User-f472068.html