MIGRATING LEGACY APPLICATIONS TO A MULTI-TENANT COMPUTING ENVIRONMENT

• US 20160261716A1
• Filed: 06/24/2015
• Published: 09/08/2016
• Est. Priority Date: 03/02/2015
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: KHALAF, Rania Y., MUTHUSAMY, Vinod, Shepard, David E., SLOMINSKI, Aleksander
• Granted Patent: US 9,973,571 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 2009/45562 Creating, deleting, cloning virtual machine instances
• CPC Class Codes: G06F 2009/4557 Distribution of virtual machine instances; Migration and load balancing
• CPC Class Codes: G06F 2009/45595 Network integration; Enabling network access in virtual machine instances
• CPC Class Codes: G06F 9/445 Program loading or initiating bootstrapping G06F9/4401; security arrangements for program loading or initiating G06F21/57
• CPC Class Codes: G06F 9/45558 Hypervisor-specific management and integration aspects
• CPC Class Codes: H04L 12/4641 Virtual LANs, VLANs, e.g. virtual private networks [VPN] LAN interconnection over a bridge based backbone H04L12/462; encapsulation techniques H04L12/4633; routing of packets H04L45/00; packet switches H04L49/00; virtual private networks for security H04L63/0272
• CPC Class Codes: H04L 67/01 Protocols
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/34 involving the movement of software or configuration parameters network booting or remote initial program loading [RIPL] G06F9/4416

Abstract

Various embodiments migrate a legacy application to a multi-tenant computing environment. In one embodiment, at least one virtualized computing container is instantiated on a host system in a multi-tenant computing environment. An instance of the legacy application is executed within the virtualized computing container. The legacy application having been initially configured to run on premise and serve one tenant at a time. The virtualized computing container securely isolates the executing instance of the legacy application from other executing instances of the legacy application. At least one request received from a first client is sent to the instance of the legacy application executing within the virtualized computing container. The virtualized computing container is quiesced based on at least one quiescing criterion having been satisfied by the instance of the legacy application.

Claims

1. A method for migrating a legacy application to a multi-tenant computing environment, the method comprising:

instantiating at least one virtualized computing container on a host system in a multi-tenant computing environment;

executing an instance of the legacy application within the virtualized computing container, the legacy application being initially configured to run on premise and serve one tenant at a time, and where the virtualized computing container securely isolates the executing instance of the legacy application from other executing instances of the legacy application;

processing, based on the executing, at least one request received from a first client by the instance of the legacy application; and

quiescing the virtualized computing container based on at least one quiescing criterion having been satisfied by the instance of the legacy application.

2. The method of claim 1, further comprising:

instantiating at least one additional virtualized computing container on the host system; and

executing an additional instance of the legacy application within the additional virtualized computing container, where the virtualized computing container serves the first client and the additional virtualized computing container serves a second client.

3. The method of claim 1, further comprising:

receiving, by a load balancer, the request from the client;

selecting, by the load balancer, at least one request dispatcher; and

sending the request to the at least one request dispatcher.

4. The method of claim 3, wherein instantiating the at least one virtualized computing container is based on:

extracting, by the request dispatcher, a tenant identifier from the request, the tenant identifier uniquely identifying the first client;

comparing, by the request dispatcher, the tenant identifier to a set of mapping information, where the set of mapping information maps each of a set of clients to at least one virtualized computing container;

determining, by the request dispatcher and based on the comparing, that a virtualized computing container fails to be mapped to the tenant identifier; and

dynamically performing the instantiating based on determining that a virtualized computing container fails to be mapped to the tenant identifier.

5. The method of claim 4, further comprising:

sending, by the request dispatcher, the request to the virtualized computing container after the container has been initialized that the instance of the legacy application has been executed.

6. The method of claim 3, further comprising:

extracting, by the request dispatcher, a tenant identifier from the request, the tenant identifier uniquely identifying the first client;

comparing, by the request dispatcher, the tenant identifier to a set of mapping information, where the set of mapping information maps each of a set of clients to at least one virtualized computing container;

determining, by the request dispatcher and based on the comparing, that the virtualized computing container is mapped to the tenant identifier; and

sending, by the request dispatcher, the request to the virtualized computing container.

7. The method of claim 1, wherein the at least one quiescing criterion comprises one of:

the instance of the legacy application performing an exit operation, the exit operation stopping executing of the instance of the legacy application; and

the instance of the legacy application comprising an idle state.

8. The method of claim 1, wherein the instance of the legacy application writes its current state to a persistent storage prior to the virtualized computing container being quiesced.

9. The method of claim 1, further comprising:

receiving the request from the client;

determining, based on an identifier within the request, that the request is state-full and related to other requests;

analyzing a set of mapping information, where the set of mapping information maps each of a set of clients to a set of virtualized computing containers and further maps each of the set of virtualized computing containers to a set of related requests;

determining, based on the analyzing, the virtualized computing container is mapped to the request; and

sending the request to the virtualized computing container based on determining that the virtualized computing container is mapped to the request.