Abstract: A method includes a processor determining a number of nodes other than the particular node from among the plurality of nodes that the particular node can communicate with at a particular point in time; determining that a number of the nodes within the plurality of nodes that the particular node can communicate with at a particular point in time is less than a value of a variable; storing in a candidate array the determined number of nodes within the plurality of nodes that the particular node can communicate with at a particular point in time which is less than the value of a variable, wherein the candidate array identifies those nodes within the plurality of nodes that can be taken to a DOWN state; and determining at least one of the nodes stored in the candidate array to be taken to a DOWN state.

Abstract: 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 a processor determining that a node which embodies the processor is in a DOWN state; determining for each of a number of remaining nodes within a plurality of nodes that each node whether each of the number of remaining 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Provided are techniques for comparing a first fileset associated with a first operating system (OS) with a second fileset associated with a second OS; determining, based upon the comparing, that the second OS is a more current version of the first OS; in response to the determining that the second OS is a more current version of the first OS, moving, in conjunction with live application mobility, a virtual machine (VM) workload partition (WPAR) on the first LPAR to a second LPAR, the moving comprising determining a set of overlays associated with the WPAR corresponding to the second OS; removing from the WPAR any overlays associated with the first OS; applying to the WPAR a set of overlays corresponding to the second OS; check pointing processes associated with the WAPR; and copying live data associated with the LPAR from the first LPAR to the second LPAR.

Abstract: Provided are techniques for comparing a first fileset associated with a first operating system (OS) with a second fileset associated with a second OS; determining, based upon the comparing, that the second OS is a more current version of the first OS; in response to the determining that the second OS is a more current version of the first OS, moving, in conjunction with live application mobility, a virtual machine (VM) workload partition (WPAR) on the first LPAR to a second LPAR, the moving comprising determining a set of overlays associated with the WPAR corresponding to the second OS; removing from the WPAR any overlays associated with the first OS; applying to the WPAR a set of overlays corresponding to the second OS; check pointing processes associated with the WPAR; and copying live data associated with the LPAR from the first LPAR to the second LPAR.

Abstract: A method, system and computer-usable medium are disclosed for managing virtual processor operations. A dynamic loader receives a request to initiate the creation of a new process, followed by a virtual processor being assigned to an isolated execution environment. The dynamic loader then initiates the creation of the new process by mapping kernel data associated with the virtual processor into the address space of the process. The dynamic loader completes the creation of the new process, and its execution is initiated within the isolated execution environment.

Abstract: According to one aspect of the present disclosure, a method and technique for communications over multiple protocol interfaces in a computing environment is disclosed. The method includes: identifying a network interface for egress data packet communications; responsive to the identified network interface differing from a data packet fragmentation technique desired for the data packet communications, deriving fragmentation data according to the desired data packet fragmentation technique; generating an application layer header for the data packet communications; storing values of the fragmentation data in select fields of the application layer header; fragmenting the data packet communications according to the desired data packet fragmentation protocol; and transmitting the data packet communications including the application layer header over the identified network interface.

Abstract: According to one aspect of the present disclosure a system and technique for communications over multiple protocol interfaces in a computing environment is disclosed. The system includes a processor and logic executable by the processor to: identify a network interface for egress data packet communications; responsive to the identified network interface differing from a data packet fragmentation technique desired for the data packet communications, derive fragmentation data according to the desired data packet fragmentation technique; generate an application layer header for the data packet communications; store values of the fragmentation data in select fields of the application layer header; fragment the data packet communications according to the desired data packet fragmentation protocol; and transmit the data packet communications including the application layer header over the identified network interface.

Abstract: According to one aspect of the present disclosure a system and technique for verifying data structure consistency across computing environments is disclosed. The system includes: a processor and a compatibility tool. The compatibility tool is executable by the processor to: generate a first signature for a data structure corresponding to a first computing environment; and generate a second signature for the data structure corresponding to a second computing environment. The processor is operable to compare the first and second signatures and, responsive to a disparity between the first and second signatures, indicate a change to the data structure between the first and second computing environments.

Abstract: 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.

Abstract: 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.

Abstract: According to one aspect of the present disclosure, a method and technique for product license management for a clustered environment having a plurality of nodes is disclosed. The method includes unlocking a product on a first node of the plurality of clustered nodes; responsive to unlocking the product on the first node, indicating an unlocked status of the product on a shared storage device accessible to the plurality of clustered nodes; and transmitting a self-unlock message from the first node to remaining nodes of the cluster to enable the remaining nodes of the cluster to self-unlock the product on the respective remaining nodes based on the status indication of the shared storage device.

Abstract: Provided are techniques for comparing a first fileset associated with a first operating system (OS) with a second fileset associated with a second OS; determining, based upon the comparing, that the second OS is a more current version of the first OS; in response to the determining that the second OS is a more current version of the first OS, moving, in conjunction with live application mobility, a virtual machine (VM) workload partition (WPAR) on the first LPAR to a second LPAR, the moving comprising determining a set of overlays associated with the WPAR corresponding to the second OS; removing from the W PAR any overlays associated with the first OS; applying to the WPAR a set of overlays corresponding to the second OS; check pointing processes associated with the WAPR; and copying live data associated with the LPAR from the first LPAR to the second LPAR.

Abstract: 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.

Abstract: 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.