# Installing OpenSearch ## Prerequisites and Setup

• uses Docker; which is why i installed Docker and wrote the Docker wiki yesterday
• [source](https://opensearch.org/docs/latest/getting-started/quickstart/)
• `sudo swapoff -a`
  • disables memory-paging and swapping
• `sudo vi /etc/sysctl.conf`
  • actually it's `/etc/sysctl.d/10-map-count.conf`
  • `vm.max_map_count=262144`
    • Set max map count to 262144
• `sudo sysctl -p`
  • reload kernel parameters

## Install Steps

• `curl -O https://raw.githubusercontent.com/opensearch-project/documentation-website/2.19/assets/examples/docker-compose.yml`
  • download the example docker-compose (which is a functional OpenSearch cluster)
• `export OPENSEARCH_INITIAL_ADMIN_PASSWORD=<admin-password>`
  • NOTE without this value the opensearch nodes will refuse to start!
  • ALSO NOTE OpenSearch has requirements for this password!
    • 8+ chars of at least 1 UPPER-CASE, 1 lower-case, 1 digit, and 1 symbol
    • and there are more undocumented rules (probably no sequences); just use a password generator
• `docker compose up -d`
  • start the docker-compose cluster as background process (`-d` = detached)
  • will download about 12 containers (two of which are 968MB and 350MB); takes a while first time

## Testing Steps

• `curl https://localhost:9200 -ku admin:<admin-password>`
  • response should confirm that the install worked
• http://localhost:5601/ should respond with dashboards and such
  • change admin-password if you like at this point

## Shooting Trouble

• `[ConnectionError]: getaddrinfo ENOTFOUND opensearch-node1`
  • check the logs of the opensearch-node1 container; likely it refused to start because the admin password didn't pass checks
  • `docker compose down` to get rid of the containers
  • `export OPENSEARCH_INITIAL_ADMIN_PASSWORD=“<something serious>“`
  • `docker compose up -d`
  • hopefully the password was sufficient to pass checks