Collect tomcat logs from tomcat docker container to Filebeat docker container - docker

Question

I have a Tomcat docker container and Filebeat docker container both are up and running.
My objective: I need to collect tomcat logs from running Tomcat container to Filebeat container.
Issue: I have no idea how to get collected log files from Tomcat container.
What I have tried so far: I have tried to create a docker volume and add tomcat logs to that volume and access that volume from filebeat container, but ended with no success.
Structure: I have wrote docker-compose.yml file under project Logstash(root directory of the project) with following project structure.(Here I want to up and run Elasticsearch, Logstash, Filebeat and Kibana docker containers from one configuration file). docker-containers(root directory of the project) with following structure (here I want to up and run Tomcat, Nginx and Postgres containers from one configuration file).
Logstash: contain 4 main sub directories (Filebeat, Logstash, Elasticsearch and Kibana), ENV file and docker-compose.yml file. Both sub directories contain Dockerfiles to pull images and build the containers.
docker-containers: contains 3 main sub directories (Tomcat, Nginx and Postgres). ENV file and docker-compose.yml file. Both sub directories contain separate Dockerfiles to pull docker image and build the container.
Note: I think this basic structure my helpful to understand my requirements.
docker-compose.yml files
Logstash.docker-compose.yml file
version: '2'
services:
elasticsearch:
container_name: OTP-Elasticsearch
build:
context: ./elasticsearch
args:
- ELK_VERSION=${ELK_VERSION}
volumes:
- ./elasticsearch/config/elasticsearch.yml:/usr/share/elasticsearch/config/elasticsearch.yml:ro
ports:
- "9200:9200"
- "9300:9300"
environment:
ES_JAVA_OPTS: "-Xmx256m -Xms256m"
networks:
- elk
filebeat:
container_name: OTP-Filebeat
command:
- "-e"
- "--strict.perms=false"
user: root
build:
context: ./filebeat
args:
- ELK_VERSION=${ELK_VERSION}
volumes:
- ./filebeat/config/filebeat.yml:/usr/share/filebeat/filebeat.yml
environment:
LS_JAVA_OPTS: "-Xmx256m -Xms256m"
networks:
- elk
depends_on:
- elasticsearch
- logstash
logstash:
container_name: OTP-Logstash
build:
context: ./logstash
args:
- ELK_VERSION=${ELK_VERSION}
volumes:
- ./logstash/config/logstash.yml:/usr/share/logstash/config/logstash.yml:ro
- ./logstash/pipeline:/usr/share/logstash/pipeline:ro
expose:
- 5044/tcp
ports:
- "9600:9600"
- "5044:5044"
environment:
LS_JAVA_OPTS: "-Xmx256m -Xms256m"
networks:
- elk
links:
- elasticsearch
depends_on:
- elasticsearch
kibana:
container_name: OTP-Kibana
build:
context: ./kibana
args:
- ELK_VERSION=${ELK_VERSION}
volumes:
- ./kibana/config/:/usr/share/kibana/config:ro
ports:
- "5601:5601"
networks:
- elk
links:
- elasticsearch
depends_on:
- elasticsearch
- logstash
- filebeat
networks:
elk:
driver: bridge
docker-containers.docker-compose.yml file
version: '2'
services:
# Nginx
nginx:
container_name: OTP-Nginx
restart: always
build:
context: ./nginx
args:
- comapanycode=${COMPANY_CODE}
- dbtype=${DB_TYPE}
- dbip=${DB_IP}
- dbname=${DB_NAME}
- dbuser=${DB_USER}
- dbpassword=${DB_PASSWORD}
- webdirectory=${WEB_DIRECTORY}
ports:
- "80:80"
links:
- db:db
volumes:
- ./log/nginx:/var/log/nginx
depends_on:
- db
# Postgres
db:
container_name: OTP-Postgres
restart: always
ports:
- "5430:5430"
build:
context: ./postgres
args:
- food_db_version=${FOOD_DB_VERSION}
- dbtype=${DB_TYPE}
- retail_db_version=${RETAIL_DB_VERSION}
- dbname=${DB_NAME}
- dbuser=${DB_USER}
- dbpassword=${DB_PASSWORD}
volumes:
- .data/db:/octopus_docker/postgresql/data
# Tomcat
tomcat:
container_name: OTP-Tomcat
restart: always
build:
context: ./tomcat
args:
- dbuser=${DB_USER}
- dbpassword=${DB_PASSWORD}
links:
- db:db
volumes:
- ./tomcat/${WARNAME}.war:/usr/local/tomcat/webapps/${WARNAME}.war
ports:
- "8080:8080"
depends_on:
- db
- nginx
Additional files:
filebeat.yml (configuration file inside Logstash/Filbeat/config/)
filebeat.inputs:
- type: log
enabled: true
paths:
- /usr/local/tomcat/logs/.*log
output.logstash:
hosts: ["logstash:5044"]
Additional Info:
System I am using is Ubuntu 18.04
My goal is to collect tomcat logs from running tomcat container and forward them to Logstash and filter logs and forward that logs to Elasticsearch and finally to Kibana for Visualization purpose.
For now I can collect local machine(host) logs and visualize them in Kibana.(/var/log/)
My Problem:
I need to know proper way to get collected tomcat logs from tomcat container and forward them to logstash container via filebeat container.
Any discussion, answer or any help to understand a way to do this is highly expected.
Thanks.

Answer 1

So loooong... Create shared volume among all containers and setup your tomcat to save log files into that folder. If you can put all services into one docker-compose.yml, just setup volume internally:
docker-compose.yml
version: '3'
services:
one:
...
volumes:
- logs:/var/log/shared
two:
...
volumes:
- logs:/var/log/shared
volumes:
logs:
If you need several docker-compose.yml files, create volume globally in advance with docker volume create logs and map it into both compose files:
version: '3'
services:
one:
...
volumes:
- logs:/var/log/shared
two:
...
volumes:
- logs:/var/log/shared
volumes:
logs:
external: true