description: Setting up ElasticSearch to search for statuses authored, favourited, or mentioned in.
description: Setting up Elasticsearch to search for statuses authored, favourited, or mentioned in.
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Mastodon supports full-text search when ElasticSearch is available. Mastodon’s full-text search allows logged in users to find results from their own statuses, their mentions, their favourites, and their bookmarks. It deliberately does not allow searching for arbitrary strings in the entire database.
Mastodon supports full-text search when Elasticsearch is available. Mastodon’s full-text search allows logged in users to find results from their own statuses, their mentions, their favourites, and their bookmarks. It deliberately does not allow searching for arbitrary strings in the entire database.
## Installing ElasticSearch {#install}
## Installing Elasticsearch {#install}
ElasticSearch requires a Java runtime. If you don’t have Java already installed, do it now. Assuming you are logged in as `root`:
Elasticsearch requires a Java runtime. If you don’t have Java already installed, do it now. Assuming you are logged in as `root`:
**Security warning:** By default, ElasticSearch is supposed to bind to localhost only, i.e. be inaccessible from the outside network. You can check which address ElasticSearch binds to by looking at `network.host` within `/etc/elasticsearch/elasticsearch.yml`. Consider that anyone who can access ElasticSearch can access and modify any data within it, as there is no authentication layer. So it’s really important that the access is secured. Having a firewall that only exposes the 22, 80 and 443 ports is advisable, as outlined in the [main installation instructions](../../prerequisites/#install-a-firewall-and-only-whitelist-ssh-http-and-https-ports). If you have a multi-host setup, you must know how to secure internal traffic.
**Security warning:** By default, Elasticsearch is supposed to bind to localhost only, i.e. be inaccessible from the outside network. You can check which address Elasticsearch binds to by looking at `network.host` within `/etc/elasticsearch/elasticsearch.yml`. Consider that anyone who can access Elasticsearch can access and modify any data within it, as there is no authentication layer. So it’s really important that the access is secured. Having a firewall that only exposes the 22, 80 and 443 ports is advisable, as outlined in the [main installation instructions](../../prerequisites/#install-a-firewall-and-only-whitelist-ssh-http-and-https-ports). If you have a multi-host setup, you must know how to secure internal traffic.
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**Security warning:** ElasticSearch versions between `2.0` and `2.14.1` are affected by an [exploit](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44228) in the `log4j` library. If affected, please refer to the [temporary mitigation](https://github.com/elastic/elasticsearch/issues/81618#issuecomment-991000240) from the ElasticSearch issue tracker.
**Security warning:** Elasticsearch versions between `2.0` and `2.14.1` are affected by an [exploit](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-44228) in the `log4j` library. If affected, please refer to the [temporary mitigation](https://github.com/elastic/elasticsearch/issues/81618#issuecomment-991000240) from the Elasticsearch issue tracker.
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To start ElasticSearch:
To start Elasticsearch:
```bash
systemctl daemon-reload
@ -56,7 +56,7 @@ ES_HOST=localhost
ES_PORT=9200
```
If you have multiple Mastodon servers on the same machine, and you are planning to use the same ElasticSearch installation for all of them, make sure that all of them have unique `REDIS_NAMESPACE` in their configurations, to differentiate the indices. If you need to override the prefix of the ElasticSearch indices, you can set `ES_PREFIX` directly.
If you have multiple Mastodon servers on the same machine, and you are planning to use the same Elasticsearch installation for all of them, make sure that all of them have unique `REDIS_NAMESPACE` in their configurations, to differentiate the indices. If you need to override the prefix of the Elasticsearch indices, you can set `ES_PREFIX` directly.
After saving the new configuration, restart Mastodon processes for it to take effect:
### Chinese search optimization {#chinese-search-optimization}
The default analyzer of the ElasticSearch is the standard analyzer, which may not be the best especially for Chinese. To improve search experience, you can install a language specific analyzer. Before creating the indices in ElasticSearch, install the following ElasticSearch extensions:
The default analyzer of the Elasticsearch is the standard analyzer, which may not be the best especially for Chinese. To improve search experience, you can install a language specific analyzer. Before creating the indices in Elasticsearch, install the following Elasticsearch extensions:
@ -790,7 +790,7 @@ Remove local thumbnails for preview cards.
### `tootctl search deploy` {#search-deploy}
Create or update an ElasticSearch index and populate it. If ElasticSearch is empty, this command will create the necessary indices and then import data from the database into those indices. This command will also upgrade indices if the underlying schema has been changed since the last run.
Create or update an Elasticsearch index and populate it. If Elasticsearch is empty, this command will create the necessary indices and then import data from the database into those indices. This command will also upgrade indices if the underlying schema has been changed since the last run.
`--batch-size`
: Defaults to 1000. A lower batch size can make ElasticSearch process records more quickly.