Migrating active I/O connections with migrating servers and clients

• US 8,898,224 B2
• Filed: 04/19/2012
• Issued: 11/25/2014
• Est. Priority Date: 08/31/2010
• Status: Expired due to Fees

• Current Assignee: AirBNB Incorporated
• Original Assignee: International Business Machines Corporation
• Inventors: Haugh, Julianne F., McBrearty, Gerald F.
• Primary Examiner(s): Cheema, Umar
• Application Number:
  US13/450,633
• Publication Number:
  US 20120209905A1
• Time in Patent Office: 950 Days
• Field of Search: None
• US Class Current: 709/203
• CPC Class Codes: G06F 3/0604 Improving or facilitating administration, e.g. storage management
• CPC Class Codes: G06F 3/0655 Vertical data movement, i.e. input-output transfer; data movement between one or more hosts and one or more storage devices
• CPC Class Codes: G06F 3/067 Distributed or networked storage systems, e.g. storage area networks [SAN], network attached storage [NAS]
• CPC Class Codes: G06F 9/5077 Logical partitioning of resources; Management or configuration of virtualized resources specific details on emulation or internal functioning of virtual machines G06F9/455
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: H04L 67/1097 for distributed storage of data in networks, e.g. transport arrangements for network file system [NFS], storage area networks [SAN] or network attached storage [NAS]

Abstract

A technique for modifying an input/output (I/O) connection type between a client and a server includes determining, by the client, when at least partial storage access control for the client is to be migrated from a first virtualized I/O server to a second virtualized I/O server. An I/O connection type, from among multiple available I/O connection types available between the client and the second virtualized I/O server, is then selected by the client when the at least partial storage access control for the client is to be migrated. The selected I/O connection type is then communicated, by the client, to the second virtualized I/O server, which is configured to facilitate storage access for the client using the selected I/O connection type.

Claims

1. A method for modifying an input/output (I/O) connection type between a client and a server, comprising:

determining, by a client, when at least partial storage access control for the client is to be migrated from a first virtualized I/O server to a second virtualized I/O server;

selecting, by the client, an I/O connection type from among multiple available I/O connection types available between the client and the second virtualized I/O server when the at least partial storage access control for the client is to be migrated; and

communicating, by the client, the selected I/O connection type to the second virtualized I/O server, wherein the second virtualized I/O server is configured to facilitate storage access for the client using the selected I/O connection type.

2. The method of claim 1, wherein the second virtualized I/O server is a replica of the first virtualized I/O server and the method further comprises:

accessing, by the client, storage via both the first and second virtualized I/O servers.

3. The method of claim 1, wherein the second virtualized I/O server resides on a different virtual host than the first virtualized I/O server and the second virtualized I/O server is further configured to facilitate storage access for the client during and following migration of the at least partial storage access control from the first virtualized I/O server to the second virtualized I/O server.

4. The method of claim 1, wherein the client includes a cluster of clients and each of the clients in the cluster is configured to select respective I/O connection types in conjunction with the other clients to balance a load on the second virtualized I/O server.

5. The method of claim 1, wherein the I/O connection type is a Fibre Channel connection, a small computer system interface (SCSI) connection, an Internet SCSI connection, or an InfiniBand connection.

6. The method of claim 1, wherein the first and second virtualized I/O servers are located in a same storage area network and the second virtualized I/O server is further configured to facilitate storage access for the client following migration of the at least partial storage access control from the first virtualized I/O server to the second virtualized I/O server.

7. The method of claim 1, wherein the selecting, by the client, an I/O connection type from among multiple available I/O connection types available between the client and the second virtualized I/O server further comprises:

testing, by the client, each of the multiple available I/O connection types to determine a performance level of each of the multiple available I/O connection types; and

selecting, by the client, the I/O connection type based on which of the multiple available I/O connection types yields a highest performance level, as indicated by the testing, and allows a connection between the client and the second virtualized I/O server to be maintained.

8. The method of claim 1, wherein the client is included in a client cluster that includes at least one other client, and wherein storage access control for the at least one other client remains under control of the first virtualized I/O server to substantially balance a load for the client cluster between the first and second virtualized I/O servers, where I/O connection types for clients in the client cluster may be the same or different.

9. The method of claim 1, wherein the client queries the second virtualized I/O server to determine the multiple available I/O connection types.

10. The method of claim 1, wherein the second virtualized I/O server is a replica of the first virtualized I/O server that is migrated to a new virtual host.