How to communicate between two services in Fargate using docker compose - elasticsearch

Question

I am trying to host Elasticsearch and kibana in AWS ECS (Fargate). I have created a docker-compose.ym file
version: '2.2'
services:
es-node:
image: docker.elastic.co/elasticsearch/elasticsearch:7.9.0
deploy:
resources:
limits:
memory: 8Gb
command: >
bash -c
'bin/elasticsearch-plugin install analysis-smartcn https://github.com/medcl/elasticsearch-analysis-stconvert/releases/download/v7.9.0/elasticsearch-analysis-stconvert-7.9.0.zip;
/usr/local/bin/docker-entrypoint.sh'
container_name: es-$ENV
environment:
- node.name=es-$ENV
- cluster.name=es-docker-cluster
- discovery.type=single-node
# - discovery.seed_hosts=es02,es03
# - cluster.initial_master_nodes=es01,es02,es03
- bootstrap.memory_lock=true
- "ES_JAVA_OPTS=-Xms512m -Xmx512m"
- ELASTIC_PASSWORD=$ES_DB_PASSWORD
- xpack.security.enabled=true
logging:
driver: awslogs
options:
awslogs-group: we-two-works-db-ecs-context
awslogs-region: us-east-1
awslogs-stream-prefix: es-node
volumes:
- elastic_data:/usr/share/elasticsearch/data
ports:
- 9200:9200
networks:
- elastic
kibana-node:
image: docker.elastic.co/kibana/kibana:7.9.0
container_name: kibana-$ENV
ports:
- 5601:5601
environment:
ELASTICSEARCH_URL: $ES_DB_URL
ELASTICSEARCH_HOSTS: '["http://es-$ENV:9200"]'
ELASTICSEARCH_USERNAME: elastic
ELASTICSEARCH_PASSWORD: $ES_DB_PASSWORD
networks:
- elastic
logging:
options:
awslogs-group: we-two-works-db-ecs-context
awslogs-region: us-east-1
awslogs-stream-prefix: "kibana-node"
volumes:
elastic_data:
driver_opts:
performance-mode: maxIO
throughput-mode: bursting
uid: 0
gid: 0
networks:
elastic:
driver: bridge
and pass in the env variables using .env.developmentfile
ENV="development"
ES_DB_URL="localhost"
ES_DB_PORT=9200
ES_DB_USER="elastic"
ES_DB_PASSWORD="****"
and up the stack in ECS using this command after creating a docker context pointing to ECS docker compose --env-file ./.env.development up
However, after creating the stack the kibana node fails to establish communication with the elasticsearch node. Check the logs from kibana node container
{
"type": "log",
"#timestamp": "2021-12-09T02:07:04Z",
"tags": [
"warning",
"plugins-discovery"
],
"pid": 7,
"message": "Expect plugin \"id\" in camelCase, but found: beats_management"
}
{
"type": "log",
"#timestamp": "2021-12-09T02:07:04Z",
"tags": [
"warning",
"plugins-discovery"
],
"pid": 7,
"message": "Expect plugin \"id\" in camelCase, but found: triggers_actions_ui"
}
[BABEL] Note: The code generator has deoptimised the styling of /usr/share/kibana/x-pack/plugins/canvas/server/templates/pitch_presentation.js as it exceeds the max of 500KB.
After doing a research I have found that ecs cli does not support service.networks docker compose file field and it has given these instructions Communication between services is implemented by SecurityGroups within the application VPC.. I am wondering how to set these instructions in the docker-compose.yml file because the IP addresses get assigned after stack is being created.

Answer 1

These containers should be able to communicate with each others via their compose service names. So for example the kibana container should be able to reach the ES node using es-node. I assume this needs you need to set ELASTICSEARCH_HOSTS: '["http://es-node:9200"]'?
I am also not sure about ELASTICSEARCH_URL: $ES_DB_URL. I see you set ES_DB_URL="localhost" but that means that the kibana container will be calling localhost to try to reach the ES service (this may work on a laptop where all containers run on a flat network but that's not how it will work on ECS - where each compose service is a separate ECS service).
[UPDATE]
I took at stab at the compose file provided. Note that I have simplified it a bit to remove some variables such as the env file, the logging entries (why did you need them? Compose/ECS will create the logging infra for you).
This file works for me (with gotchas - see below):
services:
es-node:
image: docker.elastic.co/elasticsearch/elasticsearch:7.9.0
deploy:
resources:
reservations:
memory: 8Gb
command: >
bash -c
'bin/elasticsearch-plugin install analysis-smartcn https://github.com/medcl/elasticsearch-analysis-stconvert/releases/download/v7.9.0/elasticsearch-analysis-stconvert-7.9.0.zip;
/usr/local/bin/docker-entrypoint.sh'
container_name: es-node
environment:
- node.name=es-node
- cluster.name=es-docker-cluster
- discovery.type=single-node
- bootstrap.memory_lock=true
- "ES_JAVA_OPTS=-Xms512m -Xmx512m"
- ELASTIC_PASSWORD=thisisawesome
- xpack.security.enabled=true
volumes:
- elastic_data:/usr/share/elasticsearch/data
ports:
- 9200:9200
kibana-node:
image: docker.elastic.co/kibana/kibana:7.9.0
deploy:
resources:
reservations:
memory: 8Gb
container_name: kibana-node
ports:
- 5601:5601
environment:
ELASTICSEARCH_URL: es-node
ELASTICSEARCH_HOSTS: http://es-node:9200
ELASTICSEARCH_USERNAME: elastic
ELASTICSEARCH_PASSWORD: thisisawesome
volumes:
elastic_data:
driver_opts:
performance-mode: maxIO
throughput-mode: bursting
uid: 0
gid: 0
There are two major things I had to fix:
1- the kibana task needed more horsepower (the 0.5 vCPU and 512MB of memory - default - was not enough). I set the memory to 8GB (which set the CPU to 1) and the Kibana container came up.
2- I had to increase ulimits for the ES container. Some of the error messages in the logs pointed to max file opened and vm.max_map_count which both pointed to ulimits needing being adjusted. For Fargate you need a special section in the task definition. I know there is a way to embed CFN code into the compose file via overlays but I found easier/quickert to docker compose convert the compose into a CFN file and tweak that by adding this section right below the image:
"ulimits": [
{
"name": "nofile",
"softLimit": 65535,
"hardLimit": 65535
}
]
So to recap, you'd need to take my compose above, convert it into a CFN file, add the ulimits snipped and run it directly in CFN.
You can work backwards from here to re-add your variables etc.
HTH