Active iSCSI connections

This functionality is available in Services Status > Connections

The "Active iSCSI connections" section lists initiators actively connected to the targets. The table contains the following information:

• The initiator's name is connected to the server.
• The target's name to which the initiator is connected.
• Connection IP address.
• Session ID.
• Connection ID.

To show a single session details, use the context menu. As a result, you will see the following list of parameters:

• Initiator name: Initiator name connected to the target (Target name).
• Target name: Target name to which the initiator (Initiator name) is connected.
• Initiator IP: The IP address of the initiator that is connected to the target in this session.
• SID: Session ID.
• CID: Connection ID.
• State: contains processing state of this connection.
• Reinstating: contains reinstatement state of the session.
• Bidi IO count KB (bidi_io_count_kb): Amount of data in KB transferred by the initiator since beginning or last reset.
• Bidi command count (bidi_cmd_count): Number of BIDI SCSI commands received since beginning or last reset.
• Read command count (read_cmd_count): Number of READ SCSI commands received since beginning or last reset.
• Read IO count KB (read_io_count_kb): Amount of data in KB read by the initiator since beginning or last reset.
• None command count (none_cmd_count): Number of not transferring data SCSI commands (e.g. INQUIRY or TEST UNIT READY) received since beginning or last reset.
• Write command count (write_cmd_count): Number of WRITE SCSI commands received since beginning or last reset.
• Write IO count KB (write_io_count_kb): amount of data in KB written by the initiator since beginning or last reset.
• Unknown command count (unknown_cmd_count): Number of unknown SCSI commands received since beginning or last reset .
• Commands: Contains overall number of SCSI commands in this session.
• Active commands: Contains number of active, i.e. not yet or being executed, SCSI commands in this session.
• FirstBurstLength: Specifies the maximum amount of unsolicited data an iSCSI initiator can send to the target during the execution of a single SCSI command, in bytes. This parameter is sent by both the initiator and the target, and the negotiated value used takes the minimum.
• DataDigest: Increases data integrity. When the data digest parameter is enabled, the system performs a checksum over each PDU data part. The system verifies the data using the CRC32C algorithm. This parameter is sent by the initiator and target. Checksum enablement is negotiated only if both the initiator and target intend to use CRC32c.
• HeaderDigest: Increases data integrity. When the header digest parameter is enabled, the system performs a checksum over each header part of the iSCSI Protocol Data Unit (PDU). The system verifies the data using the CRC32C algorithm. This parameter is sent by the initiator and target. Checksum enablement is negotiated only if both the initiator and target intend to use CRC32c.
• ImmediateData: This allows the initiator to append unsolicited data to a command. To achieve better performance, this should be set to "Yes". This parameter is sent by the initiator and target, and the negotiated value used is the logical product.
• InitialR2T: Turns on the default use of R2T; if disabled, allows an initiator to start sending data to a target as if it had received an initial R2T. If set to "Yes", the initiator has to wait for the target to solicit SCSI data before sending it. Setting it to "No" allows the initiator to send a burst of FirstBurstLength bytes unsolicited right after and/or (depending on the setting of ImmediateData) together with the command. Thus setting it to "No" may improve performance. This parameter is sent by the initiator and target, and the negotiated value used is the logical sum.
• MaxBurstLength: Parameter specifies the maximum amount of usable data in bytes (SCSI data payload) that can be sent in outgoing (SCSI Data-Out) or incoming (SCSI Data-In) packets. The value must be greater than or equal to the value of the FirstBurstLenght parameter.
  Configuring too large values may lead to problems allocating sufficient memory, which in turn may lead to SCSI commands timing out at the initiator host. This parameter is sent by the initiator and target, and the negotiated value used is the minimum.
• MaxOutstandingR2T: Defines the R2T (Ready to Transfer) PDUs that can be in transition before an acknowledged PDU is received.
  Controls the maximum number of data transfers the target may request at once, each of up to MaxBurstLength bytes. This parameter is sent by the initiator and target, and the negotiated used value is the minimum.
  SEE:https://kb.open-e.com/how-can-we-improve-high-latency-links-using-maxoutstandingr2t-iscsi-parameter_1083.html
• MaxRecvDataSegmentLength: Sets the maximum data segment length that can be received in an iSCSI PDU. Configuring too large values may lead to problems allocating sufficient memory, which in turn may lead to SCSI commands timing out at the initiator host. This parameter is sent by the initiator and target, and the negotiated value used is the minimum.
• MaxXmitDataSegmentLength: Sets the maximum data segment length that can be sent in any iSCSI PDU. The value actually used is the minimum of MaxXmitDataSegmentLength and the MaxRecvDataSegmentLength announced by the initiator. Configuring too large values may lead to problems allocating sufficient memory, which in turn may lead to SCSI commands timing out at the initiator host.