This default autoscaling config helps to keep some aspects of SolrCloud clean -
specifically:
* Inactive shard plan: it periodically checks whether there are old shards in
INACTIVE state that can be removed. Shards in this state are left-over parent
shards remaining after a *successful* SPLITSHARD operation (i.e. the SPLITSHARD
has completed successfully and the new sub-shards are ACTIVE and in use, and
the parent shards are no longer in use). That’s likely not your case.
* inactive markers plan has to do with Overseer state recovery when an overseer
leader crashes. Again, this likely has nothing to do with your case.
As Shawn said, logs should be able to tell you what’s really happening. For
example, there could be some wild external process in your setup that
periodically cleans up the collections :)
> On 14 Nov 2019, at 18:25, Shawn Heisey <apa...@elyograg.org> wrote:
>
> On 11/14/2019 9:17 AM, Werner Detter wrote:
>> first, thanks for your response. By "reset" I mean: collection still exists
>> but documents have been dropped (from actually round 50k to 0). It happened
>> twice within the same timeframe early in the morning the last two days so I
>> was wondering if something within Solr like this:
>> ".scheduled_maintenance":{
>> "name":".scheduled_maintenance",
>> "event":"scheduled",
>> "startTime":"NOW",
>> "every":"+1DAY",
>> "enabled":true,
>> "actions"
>> {
>> "name":"inactive_shard_plan",
>> "class":"solr.InactiveShardPlanAction"},
>> {
>> "name":"inactive_markers_plan",
>> "class":"solr.InactiveMarkersPlanAction"},
>> {
>> "name":"execute_plan",
>> "class":"solr.ExecutePlanAction"}]}},
>> could be the reason for the resets due to $something =) But I'm not sure
>> about those
>> Solr maintenance things, that's why I initially asked on the mailinglist
>> here. But
>> you said Solr doesn't contain any internal scheduling capability which means
>> this
>> is probably something else. There are no crons on the operating system
>> itself that do
>> any kind of solr maintenance.
>
> I was unaware of that config. Had to look it up. I have never looked at the
> autoscaling feature. I'm not even sure what that config will actually do.
> To me, it doesn't look like it's configured to do much.
>
> Someone who is familiar with that feature will need to chime in and
> confirm/refute my thoughts, but as far as I know, it is only capable of
> things like adding or removing replicas, not deleting the data or the index.
>
> Seeing the logs, with them set to the defaults that Solr ships, might reveal
> something.
>
> Thanks,
> Shawn
>
