International Business Machines Corporation

Michael John Snyder

Robert Dennis Miller

Kiswanto Thayib

Michael James McDermott

John J Vriezen

Cynthia Ann Rogers

Leonard William Koser

Mary Christine Manges

Frances Mary Ring

A computing system group member, signal bearing medium, and method. A configuration of a computing system group member is determined to be able to assume a role of a primary member of the computing system group and, in response thereto, a first status is assigned in the member. All members of the computing system group receive, in order, all messages directed to group members. A second status is assigned in response to determining that the configuration of the member is not able to support performance as a primary member. The member then processes, within the member, all messages that are transmitted to all members of the group when the member is assigned the first status and when the member is assigned the second status. The configuration of the member, while assigned either the first status or the second status, is adjusted based upon contents of the messages.

Ineligible group member status

A computing node that functions as a member within a computing system group, such as a cluster, that has a status allowing receipt of group messages even though the node is not an active member of the cluster. The node is able to function as a primary member or as a backup member that controls redundant resources to be utilized in case of a failure. The computing node is able to have one of two status values, an 'Active' status and an 'Ineligible' status. Members that are able to function as a primary member have an &#x201c;Active&#x201d; status assigned, and a member that is not configured or otherwise eligible to perform as a primary member is assigned an &#x201c;Ineligible&#x201d; status. Members with an Ineligible status receive all group messages and therefore are able to become configured and eligible to become a primary member.

A computing system group processing architecture that facilitates asymmetric processing at different computing nodes within a group or cluster of nodes. Nodes within a group are assigned to subgroups. Each node in a subgroup performs similar processing, but nodes in different subgroups are able to perform different processing for the same group level protocol. All nodes monitor processing completion votes that are cast by all nodes, and node in subgroups that finish processing before other subgroups synchronize to the processing of those other subgroups by casting dummy votes during vote rounds of other subgroups that are still processing their subgroup protocol.

Group synchronization by subgroups

Failover processing that accommodates failures of backup computing nodes and resources, such as data storage units and printers. Failure of a computing node that controls resources causes another computing node to assume control of the resources controlled by the failed node. Failure of the primary computing node causes another computing node, at either the same or at a different site, to be selected as the new primary node. Failure of a resource at the primary site causes the site with the next highest priority backup resource to become the new primary site. Failure of a backup computing node causes a new backup node at the same site as the failed backup node to replace the failed backup node as host for the site's resources. Backup mirroring data flows are then adjusted to reflect the new functions of the affected nodes.

Primary-backup group with backup resources failover handler

A method and apparatus is disclosed for moving a unit of data (such as an object, program, or file) from a computer operating at a current release level N to a computer operating at a previous release level N-M in a manner that assures that the unit of data will function predictably when restored to the previous release without having to make modifications or updates to the N-M level computer system. This invention allows a new release to be gradually phased in for a distributed computing system instead of requiring that all computers be upgraded to the new release before any units of data can be moved between systems.

Growing community of inventors

Lake City, MN, United States of America

Michael John Snyder