Veritas InfoScale™ 7.4.2 Virtualization Guide - Linux

To configure Veritas volume plugin with Docker 1.12 Swarm mode

1. Consider a docker swarm cluster of two nodes: docker1 and docker2.

   # docker node ls

   ID HOSTNAME STATUS AVAILABILITY MANAGER STATUS
   bd3ccjzm4qmo1ntil88r9q0la * docker1 Ready Active Leader
   d3rbrj0d4goyfckae0wozwwew docker2 Ready Active

2. Create a Veritas volume.

   # docker volume create -d veritas --name volume1 -o size=500m

3. Create a MYSQL service from the swarm manager by providing source volume name.

   Use volume1 as the source volume name that was created using the Veritas driver.

   # docker service create --replicas 1 --name sql1 --mount type=volume,source=volume1,target=/var/lib/mysql,readonly=false -e MYSQL_ROOT_PASSWORD=root123 mysql

   # docker service ps sql1

   ID NAME                   IMAGE  NODE         
   6e2dlvx27iwrgrwdcdf43u4d9 sql1.1 mysql docker1 
   
   DESIRED STATE 	CURRENT STATE 	ERROR
   Running 							Running 							44 seconds ago
   

   Where, mysql service is scheduled on node docker1.

4. Write some persistent data to the mysql database on node docker1.

   # docker ps -a

   CONTAINER ID IMAGE         COMMAND
   d844dfa66f65 mysql:latest  "docker-entrypoint.sh"
   
   CREATED        STATUS 
   A minute ago   Up    
    
   PORTS      NAMES
   3306/tcp   sql1.1.6e2dlvx27iwrgrwdcdf43u4d9
   

5. [root@docker1] # docker exec -it d844dfa66f65 bash
6. root@d844dfa66f65: /# mysql -proot123

   mysql> create database swarm_test;
   Query OK, 1 row affected (0.02 sec)
   
   mysql> use swarm_test;
   Database changed
   
   mysql> create table people (name text, age integer);
   Query OK, 0 rows affected (0.04 sec)
   
   mysql> insert into people values ('Person1', 29);
   Query OK, 1 row affected (0.00 sec)
   
   mysql> insert into people values ('Person2', 31);
   Query OK, 1 row affected (0.01 sec)
   
   mysql> select * from people;
   +---------+------+
   | name | age |
   +---------+------+
   | Person1 | 29 |
   | Person2 | 31 |
   +----------+------+
   2 rows in set (0.00 sec)
   
   

7. Simulate node failure on docker1. The MySQL service gets re-scheduled on another node by Docker Swarm.

   [root@docker1]# docker node update --availability drain docker1

8. [root@docker1]# docker service ps sql1

   ID NAME                   IMAGE        NODE
   8rofbg2td0i7oubzyxpv0kvik sql1.1 mysql docker2
   6e2dlvx27iwrgrwdcdf43u4d9 \_ sql1.1 mysql docker1
   
   DESIRED STATE CURRENT STATE ERROR
   Running 						Running 					47 seconds ago
   Shutdown 	Shutdown			about a minute ago
   

   The MySQL service gets re-scheduled on node docker2 by Docker Swarm.

9. Verify on node docker2 that container with MySQL service is created and verify updated data in the database.

   [root@docker2] # docker ps -a

   CONTAINER ID  IMAGE   COMMAND
   9fafb70c793b mysql:latest "docker-entrypoint.sh"
   
   
   CREATED 										STATUS 
   About a minute ago Up  
   
   PORTS NAMES
   3306/tcp sql1.1.8rofbg2td0i7oubzyxpv0kvik
   

   [root@docker2] # docker exec -it 9fafb70c793b bash

   root@9fafb70c793b:/# mysql -proot123

   
   mysql> use swarm_test;
   Reading table information for completion of table and column names
   You can turn off this feature to get a quicker startup with -A
   Database changed
   
   mysql> select * from people;
   +---------+------+
   | name | age |
   +---------+------+
   | Person1 | 29 |
   | Person2 | 31 |
   +----------+------+
   2 rows in set (0.00 sec)
   

   In this procedure, as InfoScale storage made data volume available on the other node, container migration operation is successful.