The index.lifecycle.origination_date setting is used in Elasticsearch's Index Lifecycle Management (ILM) to specify a custom origination date for an index. This date is used as the starting point for age-based ILM actions, allowing you to control when lifecycle transitions occur.
- Default value: Not set (uses index creation time by default)
- Possible values: Unix timestamp in milliseconds
- Recommendation: Set this value when you want to control the age calculation for ILM policies, especially for indices with historical data or when migrating from other systems.
This setting was introduced in Elasticsearch 7.5.0.
Example
To set the index.lifecycle.origination_date for a new index:
PUT /my-index
{
"settings": {
"index.lifecycle.name": "my_policy",
"index.lifecycle.origination_date": 1577836800000
}
}
This sets the origination date to January 1, 2020 (Unix timestamp: 1577836800000).
You might want to change this setting when:
- Importing historical data into a new index
- Aligning index lifecycle with business processes
- Correcting misaligned ILM transitions
The effect of this change is that ILM will use the specified date as the starting point for age calculations, potentially affecting when phase transitions occur.
Common Issues and Misuses
- Setting an incorrect timestamp format (should be in milliseconds)
- Using a future date, which may delay ILM actions unexpectedly
- Changing the date after ILM actions have already occurred, leading to confusion
Do's and Don'ts
- Do use this setting when importing historical data to ensure proper lifecycle management
- Do calculate the timestamp accurately to avoid unexpected ILM behavior
- Don't change this setting frequently, as it can lead to unpredictable ILM actions
- Don't use this setting to artificially extend the life of an index in a specific phase
Frequently Asked Questions
Q: Can I change the origination date after the index has been created?
A: Yes, you can update the setting using the index settings API, but be cautious as it may affect ongoing ILM processes.
Q: How does this setting interact with the index.creation_date?
A: The index.lifecycle.origination_date overrides the index.creation_date for ILM age calculations, but doesn't change the actual creation date of the index.
Q: What happens if I set the origination date in the future?
A: Setting a future date will delay ILM actions, as the index age will be considered negative until that date is reached.
Q: Can I use this setting with date math expressions?
A: No, the index.lifecycle.origination_date must be set as a Unix timestamp in milliseconds.
Q: How does this setting affect rollover actions in ILM?
A: The origination date doesn't directly affect rollover actions, which are typically based on index size, document count, or age since rollover, not the index origination date.
