Abstract: In one embodiment, I/O operations may be swapped from an original storage unit to a replacement storage unit in a manner which can reduce or eliminate delays caused by copying of data from the original storage unit to the replacement storage unit. A point-in-time snap copy relationship between the original storage unit and the replacement storage unit of storage locations is established and I/O operations are swapped from the original storage unit to the replacement storage unit. The I/O operations are resumed, accessing the replacement storage unit instead of the original storage unit in the input/output operations issued by the at least one host. Other aspects are described.

Abstract: In an approach for establishing metadata for one or more primary devices in a mirroring relationship, one or more computers systems generate a device validity token and establish a mirroring relationship, wherein the mirroring relationship includes identifying one or more primary devices of a plurality of devices in the mirroring relationship. The approach includes the computer systems sending the device validity token to each of a plurality of operating systems in the mirroring relationship for storage in a token store and retrieving a logical device identifier for each of the devices in the mirroring relationship. Furthermore, the approach includes the computer systems generating metadata for each of the primary devices, wherein metadata for each of the one or more primary devices includes at least the device validity token and the logical device identifier for each primary device of the one or more primary devices that generates the metadata.

Abstract: Provided are a computer program product, system, and method for establishing copy pairs from primary volumes to secondary volumes in multiple secondary storage systems for a failover session. For each of the copy pairs, data is mirrored from the primary storage system to the associated secondary storage system in the copy pair. A failure is detected at the primary storage system. Selection is made of a selected secondary storage system of the secondary storage systems in response to detecting the failure, wherein a plurality of the secondary storage systems are available for selection. The selected secondary storage system is indicated as a new primary storage system to which host requests are directed.

Abstract: A method for booting and dumping a confidential image on a trusted computer system. Embodiments of the present invention disclose deploying a secure boot image and encrypted client data from a client to a trusted computer system. Embodiments of the present invention disclose booting a confidential image on a trusted computer system. Embodiments of the present invention also disclose a process of dumping a confidential image on the trusted computer system.

Abstract: A multiple processor core computer system interface assigns instructions to partially functional processor cores based on processing resources available in each partially functional core. Each processor core is labeled as fully functional, partially functional, or non-functional, and an indicator is provided for each partially functional processor core that shows what processing resources are available for a respective core. The indicators can be stored in memory after final test. The interface can monitor cores for changes in available resources and update respective indicators, such as by superseding an existing indicator with or creating a new indicator in read-write memory.

Abstract: In one embodiment, I/O operations may be swapped from an original storage unit to a replacement storage unit in a manner which can reduce or eliminate delays caused by copying of data from the original storage unit to the replacement storage unit. A point-in-time snap copy relationship between the original storage unit and the replacement storage unit of storage locations is established and I/O operations are swapped from the original storage unit to the replacement storage unit. The I/O operations are resumed, accessing the replacement storage unit instead of the original storage unit in the input/output operations issued by the at least one host. Other aspects are described.

Abstract: A method, computer program product, and/or system for performing a selection of a plurality of auxiliary storage sites in a multi-target environment in preparation for a hyper exchange are/is provided. To perform the selection, a failure is first detected with respect to a primary storage site in the multi-target environment. Then, aggregate weights are determined based on a management policy for the plurality of auxiliary storage sites. In turn, an auxiliary storage site with a first aggregate weight is selected from the plurality of auxiliary storage sites. With the auxiliary storage site selected, the hyper exchange of a plurality of systems in a multi-target environment in response to the failure is triggered from the primary storage site to the auxiliary storage site with the first aggregate weight.

Abstract: A computer system for dumping a confidential image on a trusted computer system. A trusted computer system loads an encrypted client dumper image key. The trusted computer system decrypts, with a private host key, the encrypted client dumper image key to generate a client dumper image key. The trusted computer system loads an encrypted dumper including a client dump key, in response to determining that the client dumper image key matches a client image key which encrypts a boot image of a current operating system. The trusted computer system decrypts, with the client dumper image key, the encrypted dumper to generate a dumper including the client dump key. The trusted computer system starts the dumper. The dumper generates an encrypted dump by encrypting, with the client dump key, an image to be dumped in the secure logical partition, and the dumper writes the encrypted dump on a client dump device.

Abstract: A computer system for booting a confidential image on a trusted computer system. A trusted computer system loads an encrypted client image key onto a protected area on the trusted computer system. The trusted computer system loads an encrypted boot image onto a secure logical partition on the trusted computer system. The trusted computer system decrypts the encrypted client image key to obtain a client image key in the protected area. The trusted computer system decrypts, with the client image key, the encrypted boot image to obtain a boot image and a client data key. The trusted computer system starts the boot image, and the boot image mounts the encrypted client data onto the secure logical partition. The client data key is used by the boot image to decrypt data read from the encrypted client data and to encrypt data written to the encrypted client data.

Abstract: In one embodiment of the present description, data is migrated to a replacement source storage unit of a storage subsystem while being mirrored from the original source storage unit of a storage subsystem to an original target storage unit of a storage subsystem, and the original source storage unit and the replacement storage unit are swapped in a multi-storage volume swap to write updates to the replacement source storage unit instead of the original source storage unit, in input/output operations issued by at least one host. Further, data stored in the replacement source storage unit, is mirrored from the replacement source storage unit to the original target unit. Other aspects are described.

Abstract: A method for dumping a confidential image on a trusted computer system. A trusted computer system loads an encrypted client dumper image key. The trusted computer system decrypts, with a private host key, the encrypted client dumper image key to generate a client dumper image key. The trusted computer system loads an encrypted dumper including a client dump key, in response to determining that the client dumper image key matches a client image key which encrypts a boot image of a current operating system. The trusted computer system decrypts, with the client dumper image key, the encrypted dumper to generate a dumper including the client dump key. The trusted computer system starts the dumper. The dumper generates an encrypted dump by encrypting, with the client dump key, an image to be dumped in the secure logical partition, and the dumper writes the encrypted dump on a client dump device.

Abstract: A method for booting a confidential image on a trusted computer system. A trusted computer system loads an encrypted client image key onto a protected area on the trusted computer system. The trusted computer system loads an encrypted boot image onto a secure logical partition on the trusted computer system. The trusted computer system decrypts the encrypted client image key to obtain a client image key in the protected area. The trusted computer system decrypts, with the client image key, the encrypted boot image to obtain a boot image and a client data key. The trusted computer system starts the boot image, and the boot image mounts the encrypted client data onto the secure logical partition. The client data key is used by the boot image to decrypt data read from the encrypted client data and to encrypt data written to the encrypted client data.

Abstract: In one embodiment of the present description, data is migrated to a replacement source storage unit of a storage subsystem while being mirrored from the original source storage unit of a storage subsystem to an original target storage unit of a storage subsystem, and the original source storage unit and the replacement storage unit are swapped in a multi-storage volume swap to write updates to the replacement source storage unit instead of the original source storage unit, in input/output operations issued by at least one host. Further, data stored in the replacement source storage unit, is mirrored from the replacement source storage unit to the original target unit. Other aspects are described.

Abstract: A multiple processor core computer system interface assigns instructions to partially functional processor cores based on processing resources available in each partially functional core. Each processor core is labeled as fully functional, partially functional, or non-functional, and an indicator is provided for each partially functional processor core that shows what processing resources are available for a respective core. The indicators can be stored in memory after final test. The interface can monitor cores for changes in available resources and update respective indicators, such as by superseding an existing indicator with or creating a new indicator in read-write memory.

Abstract: A method for improving system availability in data replication environments is disclosed herein. In one embodiment, such a method includes detecting a suspend trigger, where the suspend trigger indicates that data mirroring between a primary volume and a secondary volume has been suspended. The method further detects a swap trigger some time after detecting the suspend trigger. The swap trigger indicates that I/O directed to the primary volume has failed. In the event the swap trigger is detected within a specified amount of time after detecting the suspend trigger, the method redirects I/O from the primary volume to the secondary volume. A corresponding system and computer program product are also disclosed.

Abstract: A method for improving system availability in data replication environments is disclosed herein. In one embodiment, such a method includes detecting a suspend trigger, where the suspend trigger indicates that data mirroring between a primary volume and a secondary volume has been suspended. The method further detects a swap trigger some time after detecting the suspend trigger. The swap trigger indicates that I/O directed to the primary volume has failed. In the event the swap trigger is detected within a specified amount of time after detecting the suspend trigger, the method redirects I/O from the primary volume to the secondary volume. A corresponding system and computer program product are also disclosed.

Abstract: In some embodiments of this disclosure, a computer-implemented method includes requesting, by a first thread on a computer system, conditional exclusive access to a first resource for updating the first resource to perform a first task. An indication is received that the requested exclusive access to the first resource is currently unavailable. Unconditional shared access to the first resource is requested after receiving the indication that the requested exclusive access is unavailable. The shared access to the first resource is received. The first resource is used, by a computer processor, through the shared access to perform the first task in lieu of the requested exclusive access.

Abstract: An Extended Input/output (I/O) measurement word facility is provided. Provision is made for emulation of the Extended I/O measurement word facility. The facility provides for storing measurement data associated with a single I/O operation in an extended measurement word associated with an I/O response block. In a further aspect, the stored data may have a resolution of approximately one-half microsecond.

Abstract: Provided are a computer program product, system, and method for establishing copy pairs from primary volumes to secondary volumes in multiple secondary storage systems for a failover session. For each of the copy pairs, data is mirrored from the primary storage system to the associated secondary storage system in the copy pair. A failure is detected at the primary storage system. Selection is made of a selected secondary storage system of the secondary storage systems in response to detecting the failure, wherein a plurality of the secondary storage systems are available for selection. The selected secondary storage system is indicated as a new primary storage system to which host requests are directed.

Abstract: In one embodiment, I/O operations may be swapped from an original storage unit to a replacement storage unit in a manner which can reduce or eliminate delays caused by copying of data from the original storage unit to the replacement storage unit. A point-in-time snap copy relationship between the original storage unit and the replacement storage unit of storage locations is established and I/O operations are swapped from the original storage unit to the replacement storage unit. The I/O operations are resumed, accessing the replacement storage unit instead of the original storage unit in the input/output operations issued by the at least one host. Other aspects are described.