Abstract: A computer-implemented method, according to one approach, includes: sending a notification to a host regarding a first logical unit number (LUN) in response to receiving an indication that a first node will be taken offline. The first LUN that the notification is sent to has a preferred communication path that extends through the first node. Communication paths extending through the first node are blocked and communication paths extending through a second node are promoted. Moreover, in response to determining that existing I/O operations previously assigned to the first node have been completed, the first node is taken offline. I/O operations are thereby sent to the first LUN through the second node while the first node is offline.

Abstract: A computer-implemented method, according to one approach, includes: sending a notification to a host regarding a first logical unit number (LUN) in response to receiving an indication that a first node will be taken offline. The first LUN that the notification is sent to has a preferred communication path that extends through the first node. Communication paths extending through the first node are blocked and communication paths extending through a second node are promoted. Moreover, in response to determining that existing I/O operations previously assigned to the first node have been completed, the first node is taken offline. I/O operations are thereby sent to the first LUN through the second node while the first node is offline.

Abstract: A first volume is maintained at a primary site and a second volume is maintained at a secondary site, where operations to mirror the first volume at the primary site to the second volume at the secondary site are performed while other volumes of the primary site and the secondary site are maintained in a remote copy relationship. Input/Output (I/O) operations comprising writing a metadata on the first volume at the primary site are performed and corresponding read I/O operations are performed on the second volume at the secondary site. In response to determining that the metadata read in two consecutive read I/O operations on the second volume at the secondary site does not reflect updates as requested to be made to the first volume at the primary site, determining that the primary site has failed.

Abstract: Computer-implemented methods for throttling in a multitenant environment are provided. Aspects include assigning, by a system administrator of the multitenant environment, a service level for each tenant of a plurality of tenants of the multitenant environment and obtaining a throttling value for each of a plurality of hosts associated with each of the plurality of tenants in the multitenant environment. Aspects also include monitoring, by a controller of the multitenant environment, an activity level for each of the plurality of tenants of the multitenant environment. Based on a determination that the activity level for one of the plurality of tenants has reached a maximum value specified by the service level, aspects include throttling one or more of the plurality of hosts associated with the one of the plurality of tenants based on the throttling value for the one or more of the plurality of hosts.

Abstract: Described are techniques including a computer-implemented method that comprises defining a respective priority classification for each of a plurality of sockets used for communicating between an initiator computational system and a target computational system. The method further comprises automatically assigning a respective priority classification to each of a plurality of Input/Output (IO) requests based on a type of data associated with each IO request. The method further comprises sending the plurality of IO requests to respective sockets of the plurality of sockets with a matching priority classification.

Abstract: In one embodiment, a method includes determining at least one characteristic of a plurality of ports on an individual basis. The plurality of ports are hosted by a target system and configured to send and receive data. The method also includes creating port groupings, each port grouping including one or more of the plurality of ports. Ports are grouped together in a single port grouping based on at least one shared characteristic of individual ports in the single port grouping. In addition, the method includes receiving, from an initiator port, a target discovery request at a target port of the plurality of ports. Also, the method includes determining which particular port grouping the target port belongs to. Moreover, the method includes sending information about all ports in the particular port grouping to the initiator port in response to receiving the target discovery request from the initiator port.

Abstract: Described herein are techniques for managing replication in a data storage environment. The techniques including selectively compressing and selectively encrypting, by a production site, a set of files for replication from the production site to a remote site. Files can be selectively compressed based on a compression ratio satisfying a compression threshold, and files can be selectively encrypted based on a file content satisfying an encryption criteria. The techniques can further include updating, by the production site, metadata associated with selectively compressed files and updating metadata associated with selectively encrypted files. The techniques can further include replicating the set of files for replication from the production site to the remote site, the set of files for replication including the selectively compressed and the selectively encrypted files.

Abstract: Computer implemented methods for selective data deduplication in a multitenant environment are disclosed. Data deduplication of blocks written to a storage area associated with a tenant and redundant copies of the blocks written to other storage areas of other tenants is permitted or prevented based on tagging the first storage area associated with the tenant with a particular type of parameter. Responsive to detecting a write operation directed to the storage area tagged with a parameter indicating that deduplication is not permitted, a block to be written to the storage area is modified prior to hashing the block. Responsive to detecting a write operation directed to the storage area tagged with a parameter indicating that deduplication is permitted, a block to be written to the storage area is prevented from being modified prior to hashing the block.

Abstract: Described are techniques including a computer-implemented method that comprises defining a respective priority classification for each of a plurality of sockets used for communicating between an initiator computational system and a target computational system. The method further comprises automatically assigning a respective priority classification to each of a plurality of Input/Output (IO) requests based on a type of data associated with each IO request. The method further comprises sending the plurality of IO requests to respective sockets of the plurality of sockets with a matching priority classification.

Abstract: A computer-implemented method for dynamic storage pricing in a multitenant environment is disclosed. The computer-implemented method includes dynamically modifying a storage cost for one or more tenants pointing to a block written to a storage area of the multitenant environment based, at least in part, on detecting a change in a number of tenants pointing to the block.

Abstract: Computer implemented methods for selective data deduplication in a multitenant environment are disclosed. Data deduplication of blocks written to a storage area associated with a tenant and redundant copies of the blocks written to other storage areas of other tenants is permitted or prevented based on tagging the first storage area associated with the tenant with a particular type of parameter. Responsive to detecting a write operation directed to the storage area tagged with a parameter indicating that deduplication is not permitted, a block to be written to the storage area is modified prior to hashing the block. Responsive to detecting a write operation directed to the storage area tagged with a parameter indicating that deduplication is permitted, a block to be written to the storage area is prevented from being modified prior to hashing the block.

Abstract: Described herein are techniques for managing failover in a data center environment interconnected using an internet small computer systems interface (iSCSI) communication protocol, the techniques including receiving, at a host and from a kernel driver, an asynchronous message comprising an indication of a failed path associated with a first node having a first port, a list of internet protocol (IP) addresses associated with a plurality of failover paths including a first failover path associated with a second node having a second port, and an expiration. The techniques further including performing, by the host and before the expiration, a first input/output (I/O) operation on the second port associated with the second node. The techniques further including performing, by the host and after the expiration, a second I/O operation on the first port of the first node.

Abstract: Described herein are techniques for managing replication in a data storage environment. The techniques including selectively compressing and selectively encrypting, by a production site, a set of files for replication from the production site to a remote site. Files can be selectively compressed based on a compression ratio satisfying a compression threshold, and files can be selectively encrypted based on a file content satisfying an encryption criteria. The techniques can further include updating, by the production site, metadata associated with selectively compressed files and updating metadata associated with selectively encrypted files. The techniques can further include replicating the set of files for replication from the production site to the remote site, the set of files for replication including the selectively compressed and the selectively encrypted files.

Abstract: Described herein are techniques for managing failover in a data center environment interconnected using an internet small computer systems interface (iSCSI) communication protocol, the techniques including receiving, at a host and from a kernel driver, an asynchronous message comprising an indication of a failed path associated with a first node having a first port, a list of internet protocol (IP) addresses associated with a plurality of failover paths including a first failover path associated with a second node having a second port, and an expiration. The techniques further including performing, by the host and before the expiration, a first input/output (I/O) operation on the second port associated with the second node. The techniques further including performing, by the host and after the expiration, a second I/O operation on the first port of the first node.

Abstract: In one embodiment, a method includes determining at least one characteristic of a plurality of ports on an individual basis. The plurality of ports are hosted by a target system and configured to send and receive data. The method also includes creating port groupings, each port grouping including one or more of the plurality of ports. Ports are grouped together in a single port grouping based on at least one shared characteristic of individual ports in the single port grouping. In addition, the method includes receiving, from an initiator port, a target discovery request at a target port of the plurality of ports. Also, the method includes determining which particular port grouping the target port belongs to. Moreover, the method includes sending information about all ports in the particular port grouping to the initiator port in response to receiving the target discovery request from the initiator port.