摘要:
A computer program product, an apparatus, and a method for processing communications between a target and an initiator an input/output processing system are provided. The computer program product includes a tangible storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method. The method includes: sending a message from the initiator to the target, the message requesting suspension of input/output operations between the initiator and the target for a period of time, the period of time being defined by the message; responsive to the message, suspending input/output operation messages for the period of time; performing a system change comprising at least one of: at least one update, a computer program installation, a recovery, and a change in operating parameters; and initiating new input/output operations after at least one of: expiration of the period of time and initiation of new input/output operations by the initiator.
摘要:
The state of an input/output (I/O) operation is determined in an I/O processing system. A command is received from an I/O operating system at a channel subsystem for initiating the I/O operation, a time period is for completion of the I/O operation, and the command for initiating the I/O operation is sent from the channel subsystem to the control unit. Responsive to the time period nearing elapsing without the I/O operation completing, a cancel instruction is received from the I/O operating system at the channel subsystem. Responsive to a determination by the I/O operating system to interrogate the control unit, an instruction to interrogate the control unit is received with the cancel instruction from the I/O operating system.
摘要:
Server time protocol (STP) messages and methods of exchange thereof are provided for facilitating synchronization of processing units of a timing network. The STP messages include exchange time parameters (XTP) commands and responses, and STP control (STC) commands and responses. XTP message exchange processing includes: generating an XTP message command at a first processing unit including a command transmit timestamp field set by the first processing unit and a command receive timestamp field which is unset by the first processing unit; transmitting the XTP message command to a second processing unit; setting the command receive timestamp field in the XTP command with the time the XTP command is received at the second processing unit; and generating an XTP message response at the second processing unit, the message response including the command transmit timestamp set by the first processing unit and the command receive timestamp set by the second processing unit.
摘要:
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.
摘要:
A failsafe recovery capability for a Coordinated Timing Network. The recovery capability facilitates recovery when communication is lost between two servers of the coordinated timing network. The capability includes checking another system's status in order to determine what action is to be taken. The status includes the stratum level of the servers and a version number indicating the code level of the servers.
摘要:
A computer program product, apparatus, and method are provided for determining a state of an input/output (I/O) operation in an I/O processing system. A request from a channel subsystem is received at a control unit for performing the I/O operation. After a predetermined amount of time passes without the I/O operation completing, an interrogation request is received from the channel subsystem at the control unit for determining the state of the I/O operation. A response is sent from the control unit to the channel subsystem indicating the state of the I/O operation in response to the interrogation request. The response also includes information regarding a state of an I/O device executing the I/O operation and information indicating a state of the control unit controlling the I/O device executing the I/O operation.
摘要:
A Fibre Channel over Ethernet (FCoE) device obtains knowledge of the configuration of an attached Ethernet fabric from data fields within a frame header during a fabric initialization or login (FLOGI) process. FCoE N_Ports obtain similar information during the port initialization or login (PLOGI) process. The FCoE device may provide network management services to attached FCoE devices. Embodiments include a management module or processor within an FCoE N_Port. The management module or processor receives a frame having a header and validates and extracts information associated with an Ethernet fabric from the FCoE N_Ports and in order to provide management services based on the information associated with the Ethernet fabric. The FCoE N_Port communicatively couples to at least one additional FCoE N_Port through the Ethernet fabric. The FCoE N_Ports may be implemented within a disc storage drive, a host bus adapter, and/or an FCoE switch. The capability of an N_Port to obtain this information allows a management module or processor at the N_Port to manage the Ethernet fabric.
摘要:
A primary time server of a Coordinated Timing Network remains as current time server, even if time code information of the primary time server is unavailable. The primary time server receives the necessary or desired timing information from a secondary time server and uses that information to maintain time synchronization within the Coordinated Timing Network.
摘要:
A method for detecting a switch failure and managing switch failover in a Fibre Channel over Ethernet network. The plurality of Fibre Channel over Ethernet switches are connected to an intermediary Ethernet switch and to each other via an Ethernet connection. The intermediary Ethernet switch is different from the plurality of Fibre Channel over Ethernet switches. A plurality of end polls are also connected to the intermediary Ethernet switch. A failure is detected in a first switch in the plurality of Fibre Channel over Ethernet switches. The first switch is associated with a first end port in the plurality of end ports. A failure notification is sent to the first end port using the intermediary Ethernet switch. The failure notification might specify a second switch destination and an identification of the first switch. A fabric login is exchanged between the first end port and the second switch.
摘要:
A method, system, and computer program product for providing direct communications between FCoE endpoint devices within the same fibre channel network zone. A direct fibre channel (DFC) utility provides an FCoE stack with an exclusive ability to define an Ethertype within an ethertype field of an Ethernet packet with “FCoE”. In addition, the DFC utility enables storage of access control lists (ACLs) containing allowed destination addresses and allowed source addresses within the adapter of an FCoE endpoint. Additionally, the DFC utility initiates an exchange of messages with an Ethernet switch to determine a feasibility of establishing direct connections between endpoints. In particular, the DFC utility determines whether the Ethernet switch supports FCoE ACL checking. Further, the DFC utility creates a zone ID for the FCoE endpoint device. The DFC utility allows direct communication between FCoE endpoints within the same fibre zone.