Products suddenly disappearing from Hummerce store categories is usually not an outage - it's most often a symptom of a SOLR search index rebuild running in the background, and the products come back on their own once it finishes. This entry helps you recognize the symptom, understand the cause, and temporarily restore product visibility before the rebuild completes.
Last updated: 2026-09-28.
¶ Benefits and use cases
- Fast self-diagnosis - recognizing the symptom (a SOLR index rebuild in progress) avoids an unnecessary support ticket.
- A temporary workaround without stopping sales - you can restore product visibility in categories during the index rebuild, at the cost of search and sorting.
- Predictability - the index rebuild is scheduled for the store's lowest-traffic hours, so full rebuilds rarely affect sales.
- Products stop showing up in categories, even though the store otherwise works correctly.
- A direct link to a specific product still works - the product page displays correctly.
- The task list in the panel (Status -> Tasks) shows a running SOLR index update task.
- The most common cause is the "SOLR index update" task being started manually by accident (this mainly applies to older SOLR versions). This is not a bug - the task deliberately deletes the old index and rebuilds it from scratch.
- Building the index takes anywhere from a few minutes to several hours, depending on the store and the number of indexed items.
- At the start of the rebuild, all products are missing from categories, and as indexing progresses, products gradually reappear.
- A full search index rebuild runs automatically every day at 2:00 AM, during the store's lowest-traffic hours.
- In Configuration -> Settings -> Search engine, set Items in categoryAction from SOLR to No.
- Products return to categories immediately, but bypassing SOLR search - loading items in a category will take slightly longer, and filters and sorting will not work.
- After the "SOLR index update" task finishes, you need to manually restore the Items in categoryAction from SOLR setting to Yes.
- The temporary workaround setting disables item filters and sorting in categories while it's active.
- The workaround must be manually turned off after the index rebuild finishes - the store does not do this automatically.
- We do not verify the configuration for legal compliance.
Does products disappearing from a category mean the store is down?
No. It usually means a SOLR search index rebuild is running in the background - products come back on their own once it finishes.
Does the product page also stop working during this time?
No. A direct link to the product works correctly - only the item lists within categories disappear.
How long does the index rebuild take?
From a few minutes to several hours, depending on the number of items in the store.
Can products be restored in categories before the rebuild finishes?
Yes - by setting Items in categoryAction from SOLR to No, at the cost of filters and sorting until the rebuild finishes.
How often does the store rebuild its search index?
A full index rebuild runs automatically every day at 2:00 AM.
Want to see how search works in your store? Book a free demo (in Polish).
- Task preview: Status -> Tasks - the task list, with the "SOLR index update" process running.
- Temporary workaround: Configuration -> Settings -> Search engine - the Items in categoryAction from SOLR setting.