Abstract: In some examples, a system transfers, in a first transfer operation, data of a first storage volume of a first storage location to a second storage volume for a second storage location. Responsive to a completion of the transfer of data of the first storage volume to the second storage volume, the system activates tracking information to track changes to data portions of the second storage volume, the tracking information comprising a plurality of indicators that map to respective different data portions of the second storage volume. As part of a second transfer operation following the first transfer operation, the system transfers changed data indicated by the tracking information from the second storage volume to the first storage volume, without transferring unchanged data in the second storage volume to the first storage volume.

Abstract: In some examples, for migrating data from a first storage system to a second storage system, a system creates a proxy at the first storage system to direct write requests received at the first storage system to the second storage system, initially sets a cache in the first storage system to a first state in which the cache stores write data for first write requests, and changes a state of the cache from the first state to a second state in which write data for second write requests bypasses the cache and are directed by the proxy to the second storage system.

Abstract: In some examples, for migrating data from a first storage system to a second storage system, a system creates a proxy at the first storage system to direct write requests received at the first storage system to the second storage system, initially sets a cache in the first storage system to a first state in which the cache stores write data for first write requests, and changes a state of the cache from the first state to a second state in which write data for second write requests bypasses the cache and are directed by the proxy to the second storage system.

Abstract: In some examples, a system transfers, in a first transfer operation, data of a first storage volume of a first storage location to a second storage volume for a second storage location. Responsive to a completion of the transfer of data of the first storage volume to the second storage volume, the system activates tracking information to track changes to data portions of the second storage volume, the tracking information comprising a plurality of indicators that map to respective different data portions of the second storage volume. As part of a second transfer operation following the first transfer operation, the system transfers changed data indicated by the tracking information from the second storage volume to the first storage volume, without transferring unchanged data in the second storage volume to the first storage volume.

Abstract: A gossiping scheme for sharing node status in a cluster of nodes provides a robust mechanism for determining node status within the cluster. Nodes transmit gossip messages to each other nodes, the gossip messages listing other nodes in the cluster that are operational. When a node does not receive a gossip message from a particular node within a predetermined time period, then the node transmits messages to the other nodes indicating that the particular node is down. However, if another node has received a packet from the particular node within the predetermined time period and receives the node down message, then the other node responds with a node alive message.

Abstract: Disclosed herein is a storage array configured for volume migration. An example of the storage array includes migration logic, at least partially comprising hardware logic, to establish a pass-through volume in the storage array wherein the pass-through volume is not associated with local storage in the storage array, such that communication paths between a host computing device, a source volume, and the pass-through volume during are maintained during migration. The migration logic is configured to convert the pass-through volume to a destination volume in the storage array after data migration, wherein the destination volume is associated with local storage within the storage array.

Abstract: A method, apparatus, and computer usable program product for automatic activation of roles is provided. When a user initiates an action, a set of roles needed for the action is identified. A set of roles assigned to the user is also identified. From the two sets of roles, all roles that are common to both sets are identified in a subset of roles. Roles in this subset are assigned to the user and are sufficient for the action. One or more roles from this subset of roles is selected for activation depending on system policies in effect. Selected roles are automatically activated without requiring any intervention from the user. Once the selected roles are activated, they can become inactive upon completion of the current action, or remain active for subsequent actions by the user during all or part of a user session. System policies can decide how the roles are selected for activation, and the duration of which the roles remain active once activated.

Abstract: Methods, apparatuses, and computer program products are provided for locking access to data storage shared by a plurality of compute nodes. Embodiments include maintaining, by a compute node, a queue of requests from requesting compute nodes of the plurality of compute nodes for access to the data storage, wherein possession of the queue represents possession of a mutual-exclusion lock on the data storage, the mutual-exclusion lock indicating exclusive permission for access to the data storage; and conveying, based on the order of requests in the queue, possession of the queue from the compute node to a next requesting compute node when the compute node no longer requires exclusive access to the data storage.

Abstract: Communication between clusters of processing nodes is initiated by designating a link layer address and a target node name in a remote cluster. The link layer address is transmitted to the target node via a regular network transmission. The link layer address is stored locally in each cluster and the nodes in each cluster are signaled that a configuration change has been made, so that gateway nodes in the clusters can obtain the link layer address to use for subsequent communications with the other cluster, such as event notifications of node status changes.

Abstract: A gossiping scheme for sharing node status in a cluster of nodes provides a robust mechanism for determining node status within the cluster. Nodes transmit gossip messages to each other nodes, the gossip messages listing other nodes in the cluster that are operational. When a node does not receive a gossip message from a particular node within a predetermined time period, then the node transmits messages to the other nodes indicating that the particular node is down. However, if another node has received a packet from the particular node within the predetermined time period and receives the node down message, then the other node responds with a node alive message.

Abstract: Methods, systems, and products for governing access to objects on a filesystem. In one general embodiment, the method includes providing a framework in an operating system environment for support of a plurality of access control list (ACL) types, thereby enabling governing of access to objects on a filesystem according to an associated definition of an ACL type; and accepting definitions of ACL types. The associated definition may comprise a kernel extension.

Abstract: A gossiping scheme for sharing node status in a cluster of nodes provides a robust mechanism for determining node status within the cluster. Nodes transmit gossip messages to each other nodes, the gossip messages listing other nodes in the cluster that are operational. When a node does not receive a gossip message from a particular node within a predetermined time period, then the node transmits messages to the other nodes indicating that the particular node is down. However, if another node has received a packet from the particular node within the predetermined time period and receives the node down message, then the other node responds with a node alive message.

Abstract: A second node receives a message from a first node in a cluster environment. The message includes a unique identifier of a shared data storage device including a cluster configuration database that defines membership of nodes in a cluster. In response to receiving the message, the second node attempts to find the shared data storage device. In response to finding the shared data storage device, the second node locates and reads the cluster configuration database on the shared data storage device. The second node then assimilates a cluster configuration update indicated by the cluster configuration database.

Abstract: Communication between clusters of processing nodes is initiated by designating a link layer address and a target node name in a remote cluster. The link layer address is transmitted to the target node via a regular network transmission. The link layer address is stored locally in each cluster and the nodes in each cluster are signaled that a configuration change has been made, so that gateway nodes in the clusters can obtain the link layer address to use for subsequent communications with the other cluster, such as event notifications of node status changes.

Abstract: A gossiping scheme for sharing node status in a cluster of nodes provides a robust mechanism for determining node status within the cluster. Nodes transmit gossip messages to each other nodes, the gossip messages listing other nodes in the cluster that are operational. When a node does not receive a gossip message from a particular node within a predetermined time period, then the node transmits messages to the other nodes indicating that the particular node is down. However, if another node has received a packet from the particular node within the predetermined time period and receives the node down message, then the other node responds with a node alive message.

Abstract: A system, method, and program product is provided that allows new privileges to be dynamically added to an operating system. Entities are assigned roles and these roles are associated with various authorizations. Authorizations are associated with privileges, including the new privilege. A request is received to dynamically add the new privilege to the operating system. The operating system then dynamically adds the new privilege to the system. A software service is installed that requires the new privilege. A request to execute the installed software service is received from an entity that is running on the operating system. The operating system allows the entity to execute the installed software service in response to determining that the entity has been granted the privilege. However, if the entity has not been granted the new privilege, then the operating system inhibits execution of the software service by the entity.

Abstract: Communication between clusters of processing nodes is initiated by designating a link layer address and a target node name in a remote cluster. The link layer address is transmitted to the target node via a regular network transmission. The link layer address is stored locally in each cluster and the nodes in each cluster are signaled that a configuration change has been made, so that gateway nodes in the clusters can obtain the link layer address to use for subsequent communications with the other cluster, such as event notifications of node status changes.

Abstract: Communication between clusters of processing nodes is initiated by designating a link layer address and a target node name in a remote cluster. The link layer address is transmitted to the target node via a regular network transmission. The link layer address is stored locally in each cluster and the nodes in each cluster are signaled that a configuration change has been made, so that gateway nodes in the clusters can obtain the link layer address to use for subsequent communications with the other cluster, such as event notifications of node status changes.

Abstract: Methods, systems, and products for managing memory. In one general embodiment, the method includes assigning an isolated virtual heap in a global kernel heap of a global operating system environment to each of a plurality of isolated virtual operating system environments operating in a global operating system environment; and in response to an invocation of kernel heap memory allocation from one of the isolated virtual operating system environments, dynamically allocating memory to the invoking isolated virtual operating system environment from the virtual kernel heap assigned to the invoking isolated virtual operating system environment. The method may also include running the plurality of isolated virtual operating system environments in the global operating system environment. The plurality of isolated virtual operating system environments may share a single common kernel. The isolated virtual operating system environments may run under the same operating system image.

Abstract: According to a method of access to a shared data record subject to contemporaneous read and write access by multiple requesters, a requester reads a shared data record including a payload and a first checksum. The requester calculates a second checksum of the payload of the data record. If the first and second checksums are not equal, the requester again reads the shared data record, including a third checksum, and calculates a fourth checksum of the payload of the shared data record. If the third and fourth checksums are equal, the requester processes the shared data record as valid, and if the second and fourth checksums are equal, the requester handles the shared data record as corrupt.