International Business Machines Corporation

Perinkulam I Ganesh

Esdras E Cruz-Aguilar

Khalid Filali-Adib

Frederic Barrat

Lance Warren Russell

Ravi Shankar

Madhusudanan Kandasamy

Dimpu K Nath

John Mark McConaughy

Jes Kiran Chittigala

Sungjin Yook

Vinit Jain

Mark D Rogers

Matthew Ryan Ochs

Rajeev Kumar Mishra

David W Sheffield

Laurent Dufour

Michael Burton

James Anthony Pafumi

Eric Philip Fried

David Alan Hepkin

Denise Marie Genty

Myung Mun Bae

Stephen Bailey Peckham

Marc Joel Stephenson

Nathaniel S Tomsic

Edward Shvartsman

Kavitha Ramalingam

Stephen J Tovcimak

Paul David Mazzurana

Corradino Jones

Savitri Hunasheekatti

Charles E Meyer

Christine J Wu

Christine M Briand

J Mark McConaughy

Randal Craig Swanberg

Grover Herbert Neuman

Philippe Bergheaud

Luke Mathew Browning

Balamurugan Ramajeyam

Srikanth Vishwanathan

Taru Varshney

Venkateshwar R Yerravalli

Amit Gurdasani

Luke M Browing

Michael S Fuller

Khalid Filali-Abid

A method, computer system, and computer program product area provided. A computer transmits a query command to a storage descriptor area of a first disk. The first disk belongs to a dual-site data replication system. The dual-site data replication system provides active-active access to a volume of data stored in an active disk and replicated in a backup disk. The computer receives a response to the query command. The response indicates the active disk and the backup disk for the dual-site data replication system. The computer controls an additional copy of the volume of data at a further remote site based on the active disk.

Integrating mirrored storage to remote replication site

A technique for verifying data structure consistency across computing environments includes computing a first signature for a data structure of an application subject to checkpointing corresponding to a first computing environment residing on a first computer. A second signature for the data structure of the application corresponding to a second computing environment residing on a second computer is computed. The first and second signatures are compared to determine whether a change to the data structure exists. Responsive to a lack of change to the data structure based on the comparison, a mobility operation is enabled for the application between the first computer and the second computer.

Verifying data structure consistency across computing environments

Examples of techniques for failure detection for central electronics complex (CEC) group management are described herein. An aspect includes issuing a first virtual input/output server (VIOS) probe to a hardware management console (HMC) of a central electronics complex (CEC) group. Another aspect includes receiving a first response packet that includes health data corresponding to a plurality of VIOSes. Another aspect includes determining, based on the first response packet, that cluster down is indicated on a first VIOS. Another aspect includes, based on determining that cluster down is indicated on the first VIOS, getting a VIOS state for the first VIOS from the HMC. Another aspect includes determining based on the VIOS state that the first VIOS is in a down state and determining that the first VIOS is unhealthy. Another aspect includes updating a health data entry corresponding to the first VIOS to indicate that the first VIOS is unhealthy.

Failure detection for central electronics complex group management

A processor, based on detection of a configuration change to a central electronics complex (CEC) in a CEC group, automatically creates a monitoring network within the CEC. Automatically creating the monitoring network includes the processor issuing a request via a hardware management console (HMC) to the CEC to create a virtual switch implementing a virtual local area network (VLAN). The processor also issues a request via the HMC to the CEC to create, on a virtual input-output server (VIOS) hosted in the CEC, a virtual trunk adapter connected to the VLAN. In addition, the processor issues a request via the HMC to the CEC to create, on each of a plurality of logical partitions (LPARs) hosted in the CEC, a virtual network adapter connected to the VLAN. The processor can employ the network, for example, to monitor health of the LPARs and VIOS within the CEC via the HMC.

Automated deployment of a private monitoring network

According to one aspect of the present disclosure, a method and technique for verifying data structure consistency across computing environments includes computing a first signature for a data structure of an application subject to checkpointing corresponding to a first computing environment residing on a server computer. A second signature for the data structure of the application corresponding to a second computing environment residing on a client computer is computed. The first and second signatures are compared to determine whether a change to the data structure exists. Responsive to a lack of change to the data structure based on the comparison, a mobility operation is enabled for the application between the server computer and the client computer.

Aspects of the present invention include a method, system and computer program product for handling a split condition within a computer cluster configuration. The method includes determining by a processor of a node, for each of a number of other nodes within a plurality of nodes whether each of the number of other nodes is in a DOWN state or an UP state; adding each node that is an UP state to a list of nodes that are in an UP state; adding each node that is a DOWN state to a list of nodes that are in a DOWN state; and generating a split event having two islands.

Handling a split within a clustered environment

A method and technique for communications over multiple protocol interfaces in a computing environment includes identifying a first communications protocol of a network interface for ingress data packet communications. Responsive to the identified first communications protocol of the network interface differing from a second communications protocol used for the data packet communications, fragmentation data according to a data packet fragmentation protocol corresponding to the second communications protocol is derived from an application layer header of the data packet communications. A logical packet is re-assembled from the data packet communications using the data packet fragmentation protocol and the fragmentation data.

Communications over multiple protocol interfaces in a computing environment

Examples of techniques for failure detection for central electronics complex (CEC) group management are described herein. An aspect includes issuing a first logical partition (LPAR) probe to a hardware management console (HMC) of a central electronics complex (CEC) group, wherein the CEC group comprises a plurality of LPARs. Another aspect includes receiving a first response packet from the HMC corresponding to the first LPAR probe, wherein the first response packet comprises health data corresponding to a first LPAR of the plurality of LPARs. Another aspect includes storing the health data corresponding to the first LPAR in a first health data entry corresponding to the first LPAR. Another aspect includes, for a second LPAR of the plurality of LPARs that was not included in the first response packet, updating a second health data entry corresponding to the second LPAR to indicate that the second LPAR is healthy.

A site asymmetric topology reconciliation module (SATRM) provides a stable topology for nodes located at different sites of the cluster during loss and reconnection of communication links between the sites. The SATRM monitors the cluster topology for changes in communication links between nodes. When there is an unstable cluster topology due to a loss in the communication links, the SATRM severs links to one or more sites to create a stable topology. When a communication links recovers, the SATRM merges sites to create a stable topology with the sites connected with the recovered communication links.

Site asymmetric topology reconciliation in a computer cluster

Provided are techniques for the orderly shutdown of a node within a cluster in the event of asymmetric topology maps, comprising receiving, at a first node, a plurality of heartbeats, each heartbeat corresponding to a particular, corresponding other node in the cluster and comprising information on a topological map corresponding to each particular other node's view of the cluster generating, by the first node, a topological map of the cluster based upon the information comprising the heartbeats; comparing the topological map of the cluster and the topological maps corresponding to each node; in response to a determination that the topological maps of the duster and each node are not in agreement, determining the connectivity of the first node with respect to the cluster and in respond to a determination that the first node has the lowest connectivity within the cluster, shutting down the first node.

Reconciliation of asymmetric topology in a clustered environment

According to one aspect of the present disclosure, a method and technique for verifying data structure consistency across computing environments is disclosed. The method includes: generating a first signature for a data structure corresponding to a first computing environment; generating a second signature for the data structure corresponding to a second computing environment; comparing the first and second signatures; and responsive to a disparity between the first and second signatures, indicating a change to the data structure between the first and second computing environments.

An approach is presented that provides computer clustering support across geographical boundaries. Inter-node communications are managed in a cluster by having each node operate at the network device driver (NDD) level within the kernel. Multiple types of NDD are utilized (Ethernet, SAN, DISK etc.) to provide redundancy so that nodes can reliably exchange heartbeat. To align with this architecture, for remote nodes, a pseudo NDD is used over Transmission Control Protocol (TCP) based communication interface to work along side other NDDs. Thus, the same packet which is sprayed over the NDDs pertaining to local nodes can be sprayed over the TCPSOCK NDD interface for remote nodes. Nodes (local or remote) receive the same packet and reassemble and process it in the same manner.

Clustering support across geographical boundaries

Mechanisms are provided, in a data processing system comprising a plurality of nodes, each node being a computing device, for controlling access to a critical section of code. These mechanisms send, by a sender node of the data processing system, an access request for requesting access to the critical section of code. The critical section of code is a portion of code that accesses a shared resource. The mechanisms receive, in the sender node, from a plurality of receiver nodes in the data processing system, responses to the access request. Each response in the responses includes a number of active nodes perceived by a corresponding receiver node that transmitted the response. The mechanisms control, by the sender node, access to the critical section of code based on the number of active nodes identified in each of the responses received from the receiver nodes.

Enhanced mechanisms for granting access to shared resources

Growing community of inventors

Round Rock, TX, United States of America

Perinkulam I Ganesh