From VMs to Containers: Decompose and Migrate Old Legacy JavaEE Application
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The document discusses the transition from traditional virtual machines (VMs) to container technology for decomposing and migrating legacy Java EE applications, highlighting the advantages of containers such as flexibility, resource sharing, and easier scaling. It outlines a practical scenario involving the setup of a GlassFish server and MySQL database cluster using containers, alongside features like load balancing and automated scaling. The narrative emphasizes the importance of having the right tools and planning for effective application migration and management in modern cloud environments.
![DatabaseName=MyNewDatabase
ServerName=[db hostname]
URL=jdbc:mysql://[db hostname]:3306/MyNewDatabase
Url=[same as URL]
User=[db user]
Password=[db password]](https://image.slidesharecdn.com/fromvmstocontainers-decomposeandmigrateoldlegacyjavaeeapplications-javaonesessionforslideshare-171006121431/85/From-VMs-to-Containers-Decompose-and-Migrate-Old-Legacy-JavaEE-Application-43-320.jpg)
From VMs to Containers: Decompose and Migrate Old Legacy JavaEE Application
- 1. From VMs to Containers Decompose and Migrate Old Legacy Java EE Applications
- 2. The Evolution Doesn’t Stay
- 3. VMs vs Containers on Bare Metal
- 5. Elasticity
- 6. Scalability Unlike VMs, resizing of resource limits in Containers: ● can be performed without reboot of the running instances ● easier achieved on the fly ● cheaper and faster than moving to larger VMs
- 7. Efficiency Virtual Machines Containers on Bare Metal Container technology unlocks a new level of flexibility – resources that are not consumed within the limit boundaries are automatically shared with other containers running on the same hardware node. https://www.infoq.com/articles/java-cloud-cost-reduction
- 8. Feel the Difference Resources,RAM Used Resources vs Scaling Limits
- 10. Improved CI/CD
- 11. Decomposition Splitting large monolithic application topology into small logical pieces to work with them independently
- 12. Can Seem Problematic with Legacy Applications Picture by Daniel Story
- 13. But Reachable with the Right Plan and Tools Tame Your Legacy Software Dragon!
- 14. Let’s See How This Works with GlassFish
- 15. GlassFish Server in VM
- 16. Scaling GlassFish Server in VM ● Provision a new VM with preconfigured GlassFish template ● Configure SSH connect and add this VM as an SSH Node to the DAS ● Create a new remote Worker Instance on a Node via DAS UI or asadmin CLI
- 17. Application Container + System Container Pros ● IP, hostname and local stored data survive downtimes ● No need in a port mapping ● Better isolation and virtualization of resources ● Compatible with SSH based config tools ● Provide live migration of memory state Cons ● Start-up time is slower
- 19. Scaling GlassFish in Containers Worker nodes can be added / removed automatically as well as can be attached to DAS node using container orchestration platform and a set of automation scripts
- 20. Load Balancer Adding load balancing container in front of our cluster
- 21. Database Connection ● Connect to the current database in VM ● OR decompose database to containers to gain the benefits of easy scaling and better resource utilization
- 22. DEMO
- 23. Scenario ● Create standalone GlassFish ● Create MySQL master-slave database cluster ● Connect GlassFish to Databases ● Deploy application ● Scale GlassFish and add NGINX load balancer ● Clone the environment ● Install Traffic Distributor and connect it to the two envs (original and clone)
- 24. Create Standalone GlassFish Server
- 25. Choose GlassFish and set the limits
- 27. Standalone Server > Successfully Created
- 28. Float Menu > Admin panel > Login
- 30. Credentials are in your email box
- 31. Check the nodes
- 32. Create MySQL Cluster MySQL Cluster + ProxySQL (PX)
- 34. Give a name and press “Install”
- 35. Your credentials to DB in UI and email box
- 36. Download test SQL dump NetBeans Sample App for Connection to MySQL https://netbeans.org/kb/docs/web/mysql-webapp.html
- 37. Log in to phpMyAdmin
- 38. Create a new database
- 39. Import SQL dump
- 40. Check the result
- 41. Set up JDBC connection pool
- 42. Set up JDBC connection pool
- 43. DatabaseName=MyNewDatabase ServerName=[db hostname] URL=jdbc:mysql://[db hostname]:3306/MyNewDatabase Url=[same as URL] User=[db user] Password=[db password]
- 44. Check JDBC connection pools
- 47. Download the sample application Download source and build “war” archive https://netbeans.org/kb/docs/web/mysql-webapp.html
- 48. Upload and deploy application
- 49. Press “Deploy”
- 50. Float menu > Open in browser
- 51. Good example of a legacy app
- 52. Delve into the depths of your subconscious
- 53. Check location of the deployed application
- 55. Float menu > Change the topology
- 56. Add one more GF node (1) and extra resources (2) 1 2
- 57. Log in to GlassFish admin panel
- 58. Check the nodes
- 59. Go to the cluster1 > Check the GMS
- 60. Check location of the deployed application
- 61. Clone the Environment and Add Traffic Distributor (TD)
- 62. Float menu > Clone environment
- 63. Press “Clone”
- 64. Environment has been cloned
- 65. Log in to GF admin panel of the cloned environment
- 66. Check the nodes
- 67. Marketplace > Traffic Distributor (TD)
- 68. Install TD
- 69. Press “Open in browser”
- 70. Enjoy Blue-green deployment, HA or A/B testing
- 72. Get in touch to find out more @siruslan @Jelastic