Support intro
Sorry to hear you’re facing problems. 
The community help forum (help.nextcloud.com) is for home and non-enterprise users. Support is provided by other community members on a best effort / “as available” basis. All of those responding are volunteering their time to help you.
If you’re using Nextcloud in a business/critical setting, paid and SLA-based support services can be accessed via portal.nextcloud.com where Nextcloud engineers can help ensure your business keeps running smoothly.
Getting help
In order to help you as efficiently (and quickly!) as possible, please fill in as much of the below requested information as you can.
Before clicking submit: Please check if your query is already addressed via the following resources:
- Official documentation (searchable and regularly updated)
- How to topics and FAQs
- Forum search
(Utilizing these existing resources is typically faster. It also helps reduce the load on our generous volunteers while elevating the signal to noise ratio of the forums otherwise arising from the same queries being posted repeatedly).
Some or all of the below information will be requested if it isn’t supplied; for fastest response please provide as much as you can. 
The Basics
- Nextcloud Server version (e.g., 29.x.x):
30.0.4
- Operating system and version (e.g., Ubuntu 24.04):
Amazon Linux 2023
- Web server and version (e.g, Apache 2.4.25):
Apache
- Reverse proxy and version _(e.g. nginx 1.27.2)
NginxUi
- Is this the first time you’ve seen this error? (Yes / No):
Yes
- Installation method (e.g. AlO, NCP, Bare Metal/Archive, etc.)
Docker - LinuxServer Image
- Are you using CloudfIare, mod_security, or similar? (Yes / No)
Yes
Summary of the issue you are facing:
I am trying to use FullTextSearch (Elasticsearch) in my Nextcloud instance with AWS OpneSearch/ElasticSearch service (it is a remote elasticsearch server). I have tried to use this combination but it doesn’t seem to work.
I even tried install ElasticSearch image and use it as Docker container but it does seem to work with the Nextcloud.
Everytime it shows “The client noticed that the server is not Elasticsearch and we do not support this unknown product”. I have tried using it with HTTP but it doesn’t seem to work. If I use curl https://aws-endpoint:443 it shows -
{
"name" : "REDACTED",
"cluster_name" : "REDACTED",
"cluster_uuid" : "REDACTED",
"version" : {
"distribution" : "opensearch",
"number" : "2.17.0",
"build_type" : "tar",
"build_hash" : "unknown",
"build_date" : "REDACTED",
"build_snapshot" : false,
"lucene_version" : "9.11.1",
"minimum_wire_compatibility_version" : "7.10.0",
"minimum_index_compatibility_version" : "7.0.0"
},
"tagline" : "The OpenSearch Project: https://opensearch.org/"
}
I don’t know what to do next.
Please try to solve it.
Thanks in advance.