Abstract: Embodiments of the present disclosure provide systems and methods for rebooting or halting a hung node within a logical partition cluster of a multiple processor computer system. In a disclosed embodiment, a hypervisor maintains a health monitor timer for a logical partition within a logical partition cluster. The hypervisor detects a hung node or logical partition within the logical partition cluster and provides a timely halt or reboot of the hung logical partition to avoid data corruption.

Abstract: 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.

Abstract: 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.

Abstract: A computer-implemented method according to one embodiment includes assigning a priority to virtual machines (VMs), and obtaining pathing information for the VMs. At least one of the VMs assigned a relatively higher priority is selected to perform a process over at least one of the VMs assigned a relatively lower priority. A computer program product according to another embodiment includes a computer readable storage medium having program instructions embodied therewith. The program instructions are readable and/or executable by a computer to cause the computer to perform the foregoing method. A system according to another embodiment includes a processor, and logic integrated with the processor, executable by the processor, or integrated with and executable by the processor. The logic is configured to perform the foregoing method.

Abstract: A method, system, and computer program product are disclosed. The method includes receiving a file to be printed from a device and, in response to the receiving, managing printer access for the device. Managing the printer access includes obtaining printer data from printers accessible to the device, obtaining correlation data corresponding to a printer access filter enabled on the device, filtering the printers based on the correlation data and the printer data, and inhibiting access to at least one of the printers based on the filtering.

Abstract: 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.

Abstract: 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.

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 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.

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: 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: 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: 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: 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: 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: 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: 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.