Internet Engineering Task Force (IETF) F. Knight
Request for Comments: 7144 NetApp
Category: Standards Track M. Chadalapaka
ISSN: 2070-1721 Microsoft
April 2014
Internet Engineering Task Force (IETF) F. Knight
Request for Comments: 7144 NetApp
Category: Standards Track M. Chadalapaka
ISSN: 2070-1721 Microsoft
April 2014
Internet Small Computer System Interface (iSCSI) SCSI Features Update
Internet小型计算机系统接口（iSCSI）SCSI功能更新
Abstract
摘要
Internet Small Computer System Interface (iSCSI) is a SCSI transport protocol that maps the SCSI family of protocols onto TCP/IP. The iSCSI protocol as specified in RFC 7143 (and as previously specified by the combination of RFC 3720 and RFC 5048) is based on the SAM-2 (SCSI Architecture Model - 2) version of the SCSI family of protocols. This document defines enhancements to the iSCSI protocol to support certain additional features of the SCSI protocol that were defined in SAM-3, SAM-4, and SAM-5.
Internet小型计算机系统接口（iSCSI）是一种SCSI传输协议，它将SCSI系列协议映射到TCP/IP。RFC 7143中指定的iSCSI协议（以及之前由RFC 3720和RFC 5048组合指定的协议）基于SCSI系列协议的SAM-2（SCSI体系结构模型-2）版本。本文档定义了iSCSI协议的增强功能，以支持SAM-3、SAM-4和SAM-5中定义的SCSI协议的某些附加功能。
This document is a companion document to RFC 7143.
本文件是RFC 7143的配套文件。
Status of This Memo
关于下段备忘
This is an Internet Standards Track document.
这是一份互联网标准跟踪文件。
This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Further information on Internet Standards is available in Section 2 of RFC 5741.
本文件是互联网工程任务组（IETF）的产品。它代表了IETF社区的共识。它已经接受了公众审查，并已被互联网工程指导小组（IESG）批准出版。有关互联网标准的更多信息，请参见RFC 5741第2节。
Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc7144.
有关本文件当前状态、任何勘误表以及如何提供反馈的信息，请访问http://www.rfc-editor.org/info/rfc7144.
Copyright Notice
版权公告
Copyright (c) 2014 IETF Trust and the persons identified as the document authors. All rights reserved.
版权所有（c）2014 IETF信托基金和确定为文件作者的人员。版权所有。
This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.
本文件受BCP 78和IETF信托有关IETF文件的法律规定的约束(http://trustee.ietf.org/license-info)自本文件出版之日起生效。请仔细阅读这些文件，因为它们描述了您对本文件的权利和限制。从本文件中提取的代码组件必须包括信托法律条款第4.e节中所述的简化BSD许可证文本，并提供简化BSD许可证中所述的无担保。
Table of Contents
目录
1. Introduction ....................................................4
2. Definitions, Acronyms, and Document Summary .....................4
2.1. Definitions ................................................4
2.2. Acronyms ...................................................4
2.3. New Semantics ..............................................4
3. Terminology Mapping .............................................5
4. New Feature Use .................................................7
4.1. Negotiation of New Feature Use .............................7
4.2. Impact on Standard INQUIRY Data - iSCSI Version
Descriptors ................................................8
5. SCSI Commands ...................................................9
5.1. SCSI Command Additions .....................................9
5.1.1. Command Priority (Byte 2) ..........................10
5.2. SCSI Response Additions ...................................11
5.2.1. Status Qualifier ...................................12
5.2.2. Data Segment - Sense and Response Data Segment .....12
6. Task Management Functions ......................................13
6.1. Task Management Function Request PDU ......................13
6.2. Existing Task Management Functions ........................14
6.3. Task Management Function Additions ........................14
6.3.1. LUN Field ..........................................15
6.3.2. Referenced Task Tag ................................16
6.3.3. RefCmdSN ...........................................16
6.4. Task Management Function Responses ........................17
6.4.1. Task Management Function Response PDU ..............17
6.4.2. Task Management Function Response Additions ........18
6.5. Task Management Requests Affecting Multiple Tasks .........19
7. Login/Text Operational Text Keys ...............................19
7.1. New Operational Text Keys .................................19
7.1.1. iSCSIProtocolLevel .................................19
8. Security Considerations ........................................20
9. IANA Considerations ............................................21
10. References ....................................................24
10.1. Normative References .....................................24
10.2. Informative References ...................................24
11. Acknowledgements ..............................................24
1. Introduction ....................................................4
2. Definitions, Acronyms, and Document Summary .....................4
2.1. Definitions ................................................4
2.2. Acronyms ...................................................4
2.3. New Semantics ..............................................4
3. Terminology Mapping .............................................5
4. New Feature Use .................................................7
4.1. Negotiation of New Feature Use .............................7
4.2. Impact on Standard INQUIRY Data - iSCSI Version
Descriptors ................................................8
5. SCSI Commands ...................................................9
5.1. SCSI Command Additions .....................................9
5.1.1. Command Priority (Byte 2) ..........................10
5.2. SCSI Response Additions ...................................11
5.2.1. Status Qualifier ...................................12
5.2.2. Data Segment - Sense and Response Data Segment .....12
6. Task Management Functions ......................................13
6.1. Task Management Function Request PDU ......................13
6.2. Existing Task Management Functions ........................14
6.3. Task Management Function Additions ........................14
6.3.1. LUN Field ..........................................15
6.3.2. Referenced Task Tag ................................16
6.3.3. RefCmdSN ...........................................16
6.4. Task Management Function Responses ........................17
6.4.1. Task Management Function Response PDU ..............17
6.4.2. Task Management Function Response Additions ........18
6.5. Task Management Requests Affecting Multiple Tasks .........19
7. Login/Text Operational Text Keys ...............................19
7.1. New Operational Text Keys .................................19
7.1.1. iSCSIProtocolLevel .................................19
8. Security Considerations ........................................20
9. IANA Considerations ............................................21
10. References ....................................................24
10.1. Normative References .....................................24
10.2. Informative References ...................................24
11. Acknowledgements ..............................................24
The original iSCSI protocol [RFC3720] was built based on the [SAM2] model for SCSI. Several new features and capabilities have been added to the SCSI Architecture Model in the intervening years (at the time of publication of this document, SAM-5 was the current version of the SCSI Architecture Model). This document is not a complete revision of [RFC3720]. Instead, this document is intended as a companion document to RFC 7143; this document may also be used as a companion document to the combination of [RFC3720] and [RFC5048], although both of those RFCs have been obsoleted by [RFC7143].
最初的iSCSI协议[RFC3720]是基于SCSI的[SAM2]模型构建的。在这几年中，SCSI体系结构模型增加了一些新的特性和功能（在本文档发布时，SAM-5是SCSI体系结构模型的当前版本）。本文件不是[RFC3720]的完整版本。相反，本文件旨在作为RFC 7143的配套文件；本文件也可用作[RFC3720]和[RFC5048]组合的配套文件，尽管[RFC7143]已经淘汰了这两种RFC。
For more information on the SCSI Architecture Model and SCSI Primary Commands - 4, contact the INCITS T10 Technical Committee for SCSI Storage Interfaces at <http://www.t10.org>.
有关SCSI体系结构模型和SCSI主命令-4的更多信息，请联系INCITS T10 SCSI存储接口技术委员会，网址为<http://www.t10.org>.
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this document are to be interpreted as described in [RFC2119].
本文件中的关键词“必须”、“不得”、“必需”、“应”、“不应”、“应”、“不应”、“建议”、“可”和“可选”应按照[RFC2119]中所述进行解释。
ACA Auto Contingent Allegiance AHS Additional Header Segment ISID Initiator Session Identifier LU Logical Unit PDU Protocol Data Unit SAM-5 SCSI Architecture Model - 5 (see [SAM5]) TSIH Target Session Identifying Handle
ACA自动或有效忠AHS附加头段ISID启动器会话标识符LU逻辑单元PDU协议数据单元SAM-5 SCSI体系结构模型-5（参见[SAM5]）TSIH目标会话标识句柄
This document specifies new iSCSI semantics. This section summarizes the contents of the document.
本文档指定了新的iSCSI语义。本节概述了本文件的内容。
Section 3: The mapping of iSCSI objects to SAM-5 objects The iSCSI node may contain both initiator and target capabilities.
第3节：iSCSI对象到SAM-5对象的映射iSCSI节点可能包含启动器和目标功能。
Section 4: New feature use New features need negotiation for use. The negotiation may have an impact on standard INQUIRY data.
第4节：新功能使用新功能需要协商使用。协商可能会对标准查询数据产生影响。
Section 5: New command operations The PRI field for SCSI command priority has been added to the SCSI Command PDU (see Section 5.1.1). The Status Qualifier field has been added to the SCSI Response PDU (see Section 5.2.1). Sense data may be returned (via Autosense) for any SCSI status, not just CHECK CONDITION (see Section 5.2.2).
第5节：新命令操作SCSI命令优先级的PRI字段已添加到SCSI命令PDU（请参阅第5.1.1节）。状态限定符字段已添加到SCSI响应PDU（请参阅第5.2.1节）。可针对任何SCSI状态返回检测数据（通过Autosense），而不仅仅是检查条件（见第5.2.2节）。
Section 6: New task management functions Four new task management functions (QUERY TASK, QUERY TASK SET, I_T NEXUS RESET, and QUERY ASYNCHRONOUS EVENT) have been added (see Section 6.3). A new "Function succeeded" response has been added (see Section 6.4.2).
第6节：新任务管理功能添加了四个新任务管理功能（查询任务、查询任务集、I_T NEXUS重置和查询异步事件）（请参见第6.3节）。添加了新的“功能成功”响应（见第6.4.2节）。
Section 7: New negotiation key A new negotiation key has been added to enable the use of the new features in Sections 5 and 6.
第7节：新的协商密钥添加了新的协商密钥，以便能够使用第5节和第6节中的新功能。
The iSCSI model (defined in [RFC7143]) uses different terminology than the SCSI Architecture Model. In some cases, iSCSI uses multiple terms to describe what in the SCSI Architecture Model is described with a single term. The iSCSI terms and SAM-5 terms are not necessarily equivalent, but rather, the iSCSI terms represent examples of the objects or classes described in SAM-5 as follows:
iSCSI模型（在[RFC7143]中定义）使用的术语与SCSI体系结构模型不同。在某些情况下，iSCSI使用多个术语来描述SCSI体系结构模型中使用单个术语描述的内容。iSCSI术语和SAM-5术语不一定相等，但iSCSI术语代表SAM-5中描述的对象或类的示例，如下所示：
Terminology in RFC 7143 | Terminology in SAM-5
+-----------------------------+---------------------------+
| Network Entity | none |
+-----------------------------+---------------------------+
| iSCSI Node | SCSI Device |
+-----------------------------+---------------------------+
| iSCSI Name | SCSI Device Name |
+-----------------------------+---------------------------+
| iSCSI Node Name | SCSI Device Name |
+-----------------------------+---------------------------+
| iSCSI Initiator Node | SCSI Initiator Device |
+-----------------------------+---------------------------+
| iSCSI Initiator Name | SCSI Device Name |
+-----------------------------+---------------------------+
| iSCSI Initiator Port | SCSI Initiator Port |
| Identifier; (i.e., iSCSI | Identifier |
| Node Name + ,,,i, + ISID)** | |
+-----------------------------+---------------------------+
| iSCSI Initiator Port Name; | SCSI Initiator Port Name |
| (i.e., iSCSI Node Name + | |
| ,,,i, + ISID)** | |
+-----------------------------+---------------------------+
| iSCSI Target Node | SCSI Target Device |
+-----------------------------+---------------------------+
| iSCSI Target Name | SCSI Device Name |
+-----------------------------+---------------------------+
| iSCSI Target Port | SCSI Target Port |
| Identifier; (i.e., iSCSI | Identifier |
| Node Name + ,,,t, + | |
| Target Portal Group Tag)** | |
+-----------------------------+---------------------------+
| iSCSI Target Port Name; | SCSI Target Port Name |
| (i.e., iSCSI Node Name + | |
| ,,,t, + Target Portal | |
| Group Tag)** | |
+-----------------------------+---------------------------+
| iSCSI Target Portal Group | SCSI Target Port |
+-----------------------------+---------------------------+
| iSCSI Initiator Name + | I_T Nexus Identifier |
| ',i,' + ISID + iSCSI | |
| Target Name + ',t,' + | |
| Target Portal Group Tag | |
+-----------------------------+---------------------------+
| Target Portal Group Tag | Relative Port ID |
+-----------------------------+---------------------------+
Terminology in RFC 7143 | Terminology in SAM-5
+-----------------------------+---------------------------+
| Network Entity | none |
+-----------------------------+---------------------------+
| iSCSI Node | SCSI Device |
+-----------------------------+---------------------------+
| iSCSI Name | SCSI Device Name |
+-----------------------------+---------------------------+
| iSCSI Node Name | SCSI Device Name |
+-----------------------------+---------------------------+
| iSCSI Initiator Node | SCSI Initiator Device |
+-----------------------------+---------------------------+
| iSCSI Initiator Name | SCSI Device Name |
+-----------------------------+---------------------------+
| iSCSI Initiator Port | SCSI Initiator Port |
| Identifier; (i.e., iSCSI | Identifier |
| Node Name + ,,,i, + ISID)** | |
+-----------------------------+---------------------------+
| iSCSI Initiator Port Name; | SCSI Initiator Port Name |
| (i.e., iSCSI Node Name + | |
| ,,,i, + ISID)** | |
+-----------------------------+---------------------------+
| iSCSI Target Node | SCSI Target Device |
+-----------------------------+---------------------------+
| iSCSI Target Name | SCSI Device Name |
+-----------------------------+---------------------------+
| iSCSI Target Port | SCSI Target Port |
| Identifier; (i.e., iSCSI | Identifier |
| Node Name + ,,,t, + | |
| Target Portal Group Tag)** | |
+-----------------------------+---------------------------+
| iSCSI Target Port Name; | SCSI Target Port Name |
| (i.e., iSCSI Node Name + | |
| ,,,t, + Target Portal | |
| Group Tag)** | |
+-----------------------------+---------------------------+
| iSCSI Target Portal Group | SCSI Target Port |
+-----------------------------+---------------------------+
| iSCSI Initiator Name + | I_T Nexus Identifier |
| ',i,' + ISID + iSCSI | |
| Target Name + ',t,' + | |
| Target Portal Group Tag | |
+-----------------------------+---------------------------+
| Target Portal Group Tag | Relative Port ID |
+-----------------------------+---------------------------+
** The text encoding of the ISID value and the Target Portal Group Tag value includes an initial ,,0X or ,,0x (see [RFC7143]).
**ISID值和目标门户组标记值的文本编码包括初始、0X或0X（请参阅[RFC7143]）。
The following diagram shows an example of a combination target device and initiator device. Such a configuration may exist in a target device that implements a SCSI Copy Manager. This example shows how a session that shares Network Portals within a Portal Group may be established (see Target Portal Group 1). In addition, this example shows the initiator using a different portal group than the target portal group, but the initiator portal group sharing Network Portal A with the target portal group.
下图显示了目标设备和启动器设备组合的示例。这种配置可能存在于实现SCSI拷贝管理器的目标设备中。此示例显示了如何建立在门户组内共享网络门户的会话（请参见目标门户组1）。此外，此示例显示启动器使用与目标门户组不同的门户组，但启动器门户组与目标门户组共享网络门户a。
----------------------------IP Network---------------------
| | |
+----|---------------|-------+ +----|------------+
| +----------+ +----------+ | | +----------+ |
| | Network | | Network | | | | Network | |
| | Portal A | | Portal B | | | | Portal A | |
| +----------+ +----------+ | | +----------+ |
| | Target | | | | Initiator |
| | Portal | | | | Portal |
| | Group 1 | | | | Group 2 |
+----|---------------|-------+ +----|------------+
| | |
+----------|---------------|--------------------|--------------------+
| +--------|---------------|----+ +-------------|------------------+ |
| |+-------|---------------|---+| |+------------|-----------------+| |
| ||iSCSI Session (Target side)|| ||iSCSI Session (Initiator side)|| |
| || || || || |
| || (TSIH = 56) || || (SSID = 48) || |
| |+---------------------------+| |+------------------------------+| |
| | | | | |
| | iSCSI Target Node | | iSCSI Initiator Node | |
| +-----------------------------+ +--------------------------------+ |
| iSCSI Node |
| (within Network Entity, not shown) |
+--------------------------------------------------------------------+
----------------------------IP Network---------------------
| | |
+----|---------------|-------+ +----|------------+
| +----------+ +----------+ | | +----------+ |
| | Network | | Network | | | | Network | |
| | Portal A | | Portal B | | | | Portal A | |
| +----------+ +----------+ | | +----------+ |
| | Target | | | | Initiator |
| | Portal | | | | Portal |
| | Group 1 | | | | Group 2 |
+----|---------------|-------+ +----|------------+
| | |
+----------|---------------|--------------------|--------------------+
| +--------|---------------|----+ +-------------|------------------+ |
| |+-------|---------------|---+| |+------------|-----------------+| |
| ||iSCSI Session (Target side)|| ||iSCSI Session (Initiator side)|| |
| || || || || |
| || (TSIH = 56) || || (SSID = 48) || |
| |+---------------------------+| |+------------------------------+| |
| | | | | |
| | iSCSI Target Node | | iSCSI Initiator Node | |
| +-----------------------------+ +--------------------------------+ |
| iSCSI Node |
| (within Network Entity, not shown) |
+--------------------------------------------------------------------+
The iSCSIProtocolLevel operational text key (see Section 7.1.1) containing a value of "2" MUST be negotiated to enable the use of features described in this RFC.
必须协商包含值“2”的iSCSIProtocolLevel操作文本键（见第7.1.1节），以便使用本RFC中描述的功能。
This is an iSCSI negotiation mechanism that enabled iSCSI support for corresponding SCSI capabilities (see [SAM5] and [SPC4]). For this reason, negotiation of this key to a value of "2" is necessary but not sufficient for use of the SCSI capabilities enabled by the iSCSI features in this RFC.
这是一种iSCSI协商机制，支持iSCSI支持相应的SCSI功能（请参阅[SAM5]和[SPC4]）。因此，将此密钥协商为值“2”是必要的，但不足以使用此RFC中iSCSI功能启用的SCSI功能。
For example, an iSCSI implementation may negotiate this new key to "2" but respond to the new task management functions (see Section 6.3) with "Task management function not supported" (which indicates a SCSI error that prevents the function from being performed). In contrast, if the key is negotiated to "2", an iSCSI implementation MUST NOT reject a Task Management Function Request PDU that requests one of the new task management functions (as such a reject would report an iSCSI protocol error).
例如，iSCSI实现可能会将此新密钥协商为“2”，但对新的任务管理功能（请参阅第6.3节）的响应为“不支持任务管理功能”（这表示SCSI错误，该错误阻止了该功能的执行）。相反，如果密钥协商为“2”，则iSCSI实施不得拒绝请求新任务管理功能之一的任务管理功能请求PDU（因为拒绝会报告iSCSI协议错误）。
The negotiated value of the iSCSIProtocolLevel key is an increment from the base iSCSI version descriptor value (0960h); see [SPC4]. If the SCSI device server returns an iSCSI version descriptor in the standard INQUIRY data, then the value returned in that iSCSI version descriptor MUST be set to the sum of the base value (0960h) plus the negotiated value of the iSCSIProtocolLevel key. (For example, if the negotiated iSCSIProtocolLevel=2, then if an iSCSI version descriptor is returned in the standard INQUIRY data, it is set to 0962h.)
iSCSIProtocolLevel密钥的协商值是基本iSCSI版本描述符值（0960h）的增量；见[SPC4]。如果SCSI设备服务器在标准查询数据中返回iSCSI版本描述符，则该iSCSI版本描述符中返回的值必须设置为基本值（0960h）加上iSCSIProtocolLevel密钥的协商值之和。（例如，如果协商的iSCSIProtocolLevel=2，则如果在标准查询数据中返回iSCSI版本描述符，则将其设置为0962h。）
In support of this functionality, INCITS Technical Committee T10, which is responsible for SCSI standards, has assigned SCSI version descriptor codes 0961h-097Fh to RFC 7144 for IANA to manage via the values 1-31 of the iSCSIProtocolLevel key; see Section 9. The "No version claimed" description for the value 0 of the iSCSIProtocolLevel key corresponds to the existing T10 assignment of the 0960h SCSI version descriptor code to "iSCSI (no version claimed)" -- for this reason, the assignment of the value 0 in the IANA registry for the iSCSIProtocolLevel key must not be changed.
为支持此功能，负责SCSI标准的INCITS技术委员会T10已将SCSI版本描述符代码0961h-097Fh分配给RFC 7144，以便IANA通过iSCSIProtocolLevel密钥的值1-31进行管理；见第9节。iSCSIProtocolLevel项的值0的“未声明版本”描述对应于0960h SCSI版本描述符代码对“iSCSI（未声明版本）”的现有T10分配——因此，不得更改IANA注册表中iSCSIProtocolLevel项的值0分配。
The format of the SCSI Command PDU is:
SCSI命令PDU的格式为：
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|I| 0x01 |F|R|W|. .|ATTR | PRI | Reserved |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+---------------+---------------+---------------+---------------+
8| Logical Unit Number (LUN) |
+ +
12| |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20| Expected Data Transfer Length |
+---------------+---------------+---------------+---------------+
24| CmdSN |
+---------------+---------------+---------------+---------------+
28| ExpStatSN |
+---------------+---------------+---------------+---------------+
32/ SCSI Command Descriptor Block (CDB) /
+/ /
+---------------+---------------+---------------+---------------+
48/ AHS (Optional) /
+---------------+---------------+---------------+---------------+
x/ Header Digest (Optional) /
+---------------+---------------+---------------+---------------+
y/ (DataSegment, Command Data) (Optional) /
+/ /
+---------------+---------------+---------------+---------------+
z/ Data Digest (Optional) /
+---------------+---------------+---------------+---------------+
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|I| 0x01 |F|R|W|. .|ATTR | PRI | Reserved |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+---------------+---------------+---------------+---------------+
8| Logical Unit Number (LUN) |
+ +
12| |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20| Expected Data Transfer Length |
+---------------+---------------+---------------+---------------+
24| CmdSN |
+---------------+---------------+---------------+---------------+
28| ExpStatSN |
+---------------+---------------+---------------+---------------+
32/ SCSI Command Descriptor Block (CDB) /
+/ /
+---------------+---------------+---------------+---------------+
48/ AHS (Optional) /
+---------------+---------------+---------------+---------------+
x/ Header Digest (Optional) /
+---------------+---------------+---------------+---------------+
y/ (DataSegment, Command Data) (Optional) /
+/ /
+---------------+---------------+---------------+---------------+
z/ Data Digest (Optional) /
+---------------+---------------+---------------+---------------+
The SCSI Command PDU above is duplicated from [RFC7143] for reference to show the PRI field. For any field other than the PRI field, the text in [RFC7143] supersedes the text in Section 5.1 of this document in the event the two documents conflict.
上面的SCSI命令PDU从[RFC7143]复制，以供参考，以显示PRI字段。对于PRI字段以外的任何字段，如果两个文件发生冲突，[RFC7143]中的文本将取代本文件第5.1节中的文本。
The Command Priority (PRI) is a four-bit field that specifies the relative scheduling importance of this command in relation to other commands already in the task set with SIMPLE task attributes (see [SAM5]).
命令优先级（PRI）是一个四位字段，用于指定此命令相对于具有简单任务属性的任务集中已有的其他命令的相对调度重要性（请参见[SAM5]）。
Section 11 ("iSCSI PDU Formats") of [RFC7143] requires that senders set this field to zero. A sender MUST NOT set this field to a value other than zero unless the iSCSIProtocolLevel text key defined in Section 7.1.1 has been negotiated on the session with a value of "2".
[RFC7143]的第11节（“iSCSI PDU格式”）要求发送方将此字段设置为零。发送方不得将此字段设置为零以外的值，除非第7.1.1节中定义的iSCSIProtocolLevel文本键已在会话中协商为值“2”。
This field MUST be ignored by iSCSI targets unless the iSCSIProtocolLevel text key with a value of "2" as defined in Section 7.1.1 was negotiated on the session.
iSCSI目标必须忽略此字段，除非会话中协商了值为“2”的iSCSIProtocolLevel文本键（如第7.1.1节所定义）。
See [SAM5] for additional considerations on the use of the Command Priority field.
有关使用命令优先级字段的其他注意事项，请参见[SAM5]。
The format of the SCSI Response PDU is:
SCSI响应PDU的格式为：
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|.| 0x21 |1|. .|o|u|O|U|.| Response | Status |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+---------------+---------------+---------------+---------------+
8| Status Qualifier | Reserved |
+---------------+---------------+---------------+---------------+
12| Reserved |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20| SNACK Tag or Reserved |
+---------------+---------------+---------------+---------------+
24| StatSN |
+---------------+---------------+---------------+---------------+
28| ExpCmdSN |
+---------------+---------------+---------------+---------------+
32| MaxCmdSN |
+---------------+---------------+---------------+---------------+
36| ExpDataSN or Reserved |
+---------------+---------------+---------------+---------------+
40| Bidirectional Read Residual Count or Reserved |
+---------------+---------------+---------------+---------------+
44| Residual Count or Reserved |
+---------------+---------------+---------------+---------------+
48| Header-Digest (Optional) |
+---------------+---------------+---------------+---------------+
/ Data Segment (Optional) /
+/ /
+---------------+---------------+---------------+---------------+
| Data-Digest (Optional) |
+---------------+---------------+---------------+---------------+
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|.| 0x21 |1|. .|o|u|O|U|.| Response | Status |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+---------------+---------------+---------------+---------------+
8| Status Qualifier | Reserved |
+---------------+---------------+---------------+---------------+
12| Reserved |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20| SNACK Tag or Reserved |
+---------------+---------------+---------------+---------------+
24| StatSN |
+---------------+---------------+---------------+---------------+
28| ExpCmdSN |
+---------------+---------------+---------------+---------------+
32| MaxCmdSN |
+---------------+---------------+---------------+---------------+
36| ExpDataSN or Reserved |
+---------------+---------------+---------------+---------------+
40| Bidirectional Read Residual Count or Reserved |
+---------------+---------------+---------------+---------------+
44| Residual Count or Reserved |
+---------------+---------------+---------------+---------------+
48| Header-Digest (Optional) |
+---------------+---------------+---------------+---------------+
/ Data Segment (Optional) /
+/ /
+---------------+---------------+---------------+---------------+
| Data-Digest (Optional) |
+---------------+---------------+---------------+---------------+
The SCSI Response PDU above is duplicated from [RFC7143] for reference to show the Status Qualifier field. For any field other than the Status field, the Status Qualifier field, and the Data Segment - Sense and Response Data Segment field, the text in [RFC7143] supersedes the text in Section 5.2 of this document in the event the two documents conflict.
上面的SCSI响应PDU从[RFC7143]复制以供参考，以显示状态限定符字段。对于除状态字段、状态限定符字段和数据段-检测和响应数据段字段以外的任何字段，[RFC7143]中的文本将在两个文档发生冲突时取代本文档第5.2节中的文本。
The Status Qualifier provides additional status information (see [SAM5]).
状态限定符提供额外的状态信息（请参见[SAM5]）。
As defined in Section 11 ("iSCSI PDU Formats") of [RFC7143], compliant senders already set this field to zero. Compliant senders MUST NOT set this field to a value other than zero unless the iSCSIProtocolLevel text key with a value of "2" as defined in Section 7.1.1 was negotiated on the session.
如[RFC7143]第11节（“iSCSI PDU格式”）中所定义，符合要求的发送方已将此字段设置为零。符合要求的发件人不得将此字段设置为零以外的值，除非在会话中协商了值为“2”（如第7.1.1节所定义）的iSCSIProtocolLevel文本键。
This field MUST be ignored by receivers unless the iSCSIProtocolLevel text key with a value of "2" as defined in Section 7.1.1 was negotiated on the session.
接收方必须忽略此字段，除非会话中协商了值为“2”（如第7.1.1节所定义）的iSCSIProtocolLevel文本键。
Section 11.4.7 of [RFC7143] specifies that iSCSI targets MUST support and enable Autosense. If Status is CHECK CONDITION (0x02), then the Data Segment MUST contain sense data for the failed command. While [RFC7143] does not make any statements about the state of the Data Segment when the Status is not CHECK CONDITION (0x02) (i.e., the Data Segment is not prohibited from containing sense data when the Status is not CHECK CONDITION), negotiation of the iSCSIProtocolLevel text key with a value of "2" as defined in Section 7.1.1 explicitly indicates that the Data Segment MAY contain sense data at any time, no matter what value is set in the Status field.
[RFC7143]第11.4.7节规定iSCSI目标必须支持并启用Autosense。如果状态为检查条件（0x02），则数据段必须包含失败命令的检测数据。虽然[RFC7143]未对状态为非检查条件（0x02）时的数据段状态做出任何声明（即，当状态为非检查条件时，数据段不禁止包含检测数据），但协商值为“2”的iSCSIProtocolLevel文本键如第7.1.1节所定义，明确指出无论状态字段中设置了什么值，数据段随时可能包含检测数据。
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|I| 0x02 |1| Function | Reserved |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+---------------+---------------+---------------+---------------+
8| Logical Unit Number (LUN) |
+ +
12| |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20| Referenced Task Tag or 0xffffffff |
+---------------+---------------+---------------+---------------+
24| CmdSN |
+---------------+---------------+---------------+---------------+
28| ExpStatSN |
+---------------+---------------+---------------+---------------+
32| RefCmdSN or Reserved |
+---------------+---------------+---------------+---------------+
36| ExpDataSN or Reserved |
+---------------+---------------+---------------+---------------+
40| Reserved /
+/ /
+---------------+---------------+---------------+---------------+
48| Header-Digest (Optional) |
+---------------+---------------+---------------+---------------+
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|I| 0x02 |1| Function | Reserved |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+---------------+---------------+---------------+---------------+
8| Logical Unit Number (LUN) |
+ +
12| |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20| Referenced Task Tag or 0xffffffff |
+---------------+---------------+---------------+---------------+
24| CmdSN |
+---------------+---------------+---------------+---------------+
28| ExpStatSN |
+---------------+---------------+---------------+---------------+
32| RefCmdSN or Reserved |
+---------------+---------------+---------------+---------------+
36| ExpDataSN or Reserved |
+---------------+---------------+---------------+---------------+
40| Reserved /
+/ /
+---------------+---------------+---------------+---------------+
48| Header-Digest (Optional) |
+---------------+---------------+---------------+---------------+
The Task Management Function Request PDU above is duplicated from [RFC7143] for reference only. [RFC7143] supersedes the text in Sections 6.1 and 6.2 of this document in the event the two documents conflict.
上述任务管理功能请求PDU从[RFC7143]复制，仅供参考。[RFC7143]在两个文件发生冲突时，将取代本文件第6.1节和第6.2节中的文本。
Section 11.5 of [RFC7143] defines the semantics used to request that SCSI task management functions be performed. The following task management functions are defined:
[RFC7143]第11.5节定义了用于请求执行SCSI任务管理功能的语义。定义了以下任务管理功能：
1 - ABORT TASK 2 - ABORT TASK SET 3 - CLEAR ACA 4 - CLEAR TASK SET 5 - LOGICAL UNIT RESET 6 - TARGET WARM RESET 7 - TARGET COLD RESET 8 - TASK REASSIGN
1-中止任务2-中止任务集3-清除ACA 4-清除任务集5-逻辑单元重置6-目标热重置7-目标冷重置8-任务重新分配
Additional task management function codes are listed below. For a more detailed description of SCSI task management, see [SAM5].
下面列出了其他任务管理功能代码。有关SCSI任务管理的更详细说明，请参阅[SAM5]。
9 - QUERY TASK - determine if the command identified by the Referenced Task Tag field is present in the task set.
9-查询任务-确定任务集中是否存在由引用的任务标记字段标识的命令。
10 - QUERY TASK SET - determine if any command is present in the task set for the I_T_L Nexus on which the task management function was received.
10-查询任务集-确定接收任务管理功能的I_T_L Nexus的任务集中是否存在任何命令。
11 - I_T NEXUS RESET - perform an I_T nexus loss function (see [SAM5]) for the I_T nexus on which the task management function was received.
11-I_T NEXUS RESET-对接收到任务管理功能的I_T NEXUS执行I_T NEXUS丢失功能（参见[SAM5]）。
12 - QUERY ASYNCHRONOUS EVENT - determine if there is a unit attention condition or a deferred error pending for the I_T_L nexus on which the task management function was received.
12-查询异步事件-确定接收任务管理功能的I_T_L nexus是否存在单位注意条件或延迟错误挂起。
These task management function requests MUST NOT be sent unless the iSCSIProtocolLevel text key with a value of "2" as defined in Section 7.1.1 was negotiated on the session.
除非在会话中协商了第7.1.1节中定义的值为“2”的iSCSIProtocolLevel文本键，否则不得发送这些任务管理功能请求。
Any compliant initiator that sends any of the new task management functions defined in this section MUST also support all new task management function responses (as specified in Section 6.4.2).
发送本节中定义的任何新任务管理功能的任何合规启动器也必须支持所有新任务管理功能响应（如第6.4.2节所述）。
For all of the task management functions detailed in this section, the Task Management Function Response MUST be returned as detailed in Section 6.4.
对于本节详述的所有任务管理功能，必须按照第6.4节详述的内容返回任务管理功能响应。
The iSCSI target MUST ensure that no responses for the commands covered by a task management function are sent to the iSCSI initiator port after the Task Management response except for commands covered by a TASK REASSIGN, QUERY TASK, or QUERY TASK SET.
iSCSI目标必须确保在任务管理响应之后，除任务重新分配、查询任务或查询任务集包含的命令外，任务管理功能包含的命令没有响应发送到iSCSI启动器端口。
If a QUERY TASK is issued for a task created by an immediate command, then RefCmdSN MUST be that of the Task Management request itself (i.e., CmdSN and RefCmdSN are equal); otherwise, RefCmdSN MUST be set to the CmdSN of the task to be queried (lower than CmdSN).
如果为即时命令创建的任务发出查询任务，则RefCmdSN必须是任务管理请求本身的查询任务（即，CmdSN和RefCmdSN相等）；否则，必须将RefCmdSN设置为要查询的任务的CmdSN（低于CmdSN）。
If the connection is still active (it is not undergoing an implicit or explicit logout), QUERY TASK MUST be issued on the same connection to which the task to be queried is allegiant at the time the Task Management request is issued. If the connection is implicitly or explicitly logged out (i.e., no other request will be issued on the failing connection and no other response will be received on the failing connection), then a QUERY TASK function request may be issued on another connection. This Task Management request will then establish a new allegiance for the command being queried.
如果连接仍处于活动状态（未进行隐式或显式注销），则在发出任务管理请求时，必须在要查询的任务为allegiant的同一连接上发出查询任务。如果连接隐式或显式注销（即，故障连接上不会发出其他请求，故障连接上也不会收到其他响应），则可以在另一个连接上发出查询任务功能请求。然后，此任务管理请求将为所查询的命令建立新的效忠关系。
At the target, a QUERY TASK function MUST NOT be executed on a Task Management request; such a request MUST result in Task Management response of "Function rejected".
在目标，查询任务功能不能对任务管理请求执行；此类请求必须导致任务管理响应“功能被拒绝”。
For the I_T NEXUS RESET function, the target device MUST respond to the function as defined in [SAM5]. Each logical unit accessible via the receiving I_T NEXUS MUST behave as dictated by the I_T nexus loss function in [SAM5] for the I_T nexus on which the task management function was received. The target device MUST drop all connections in the session over which this function is received. Independent of the DefaultTime2Wait and DefaultTime2Retain values applicable to the session over which this function is received, the target device MUST consider each participating connection in the session to have immediately timed out, leading to FREE state. The resulting timeouts cause the session timeout event defined in [RFC7143], which in turn triggers the I_T nexus loss notification to the SCSI layer as described in [RFC7143].
对于I_T NEXUS重置功能，目标设备必须响应[SAM5]中定义的功能。对于接收任务管理功能的I_T NEXUS，通过接收I_T NEXUS可访问的每个逻辑单元必须按照[SAM5]中的I_T NEXUS loss函数的指示运行。目标设备必须断开接收此功能的会话中的所有连接。独立于DeFultTime2Audio和Debug Time2F留铁值，该值适用于接收该函数的会话，目标设备必须考虑会话中的每个参与连接以立即超时，从而导致空闲状态。由此产生的超时会导致[RFC7143]中定义的会话超时事件，这反过来会触发到SCSI层的I_T nexus丢失通知，如[RFC7143]中所述。
This field is required for functions that address a specific LU (i.e., ABORT TASK, CLEAR TASK SET, ABORT TASK SET, CLEAR ACA, LOGICAL UNIT RESET, QUERY TASK, QUERY TASK SET, and QUERY ASYNCHRONOUS EVENT) and is reserved in all others.
处理特定LU（即中止任务、清除任务集、中止任务集、清除ACA、逻辑单元重置、查询任务、查询任务集和查询异步事件）的函数需要此字段，并且在所有其他函数中保留此字段。
The Reference Task Tag is the Initiator Task Tag of the task to be aborted for the ABORT TASK function, reassigned for the TASK REASSIGN function, or queried for the QUERY TASK function. For all other functions, this field MUST be set to the reserved value 0xffffffff.
参考任务标记是要为“中止任务”功能中止、为“任务重新分配”功能重新分配或为“查询任务”功能查询的任务的启动器任务标记。对于所有其他函数，此字段必须设置为保留值0xFFFFFF。
If a QUERY TASK is issued for a task created by an immediate command then RefCmdSN MUST be that of the Task Management request itself (i.e., CmdSN and RefCmdSN are equal).
如果为立即命令创建的任务发出查询任务，则RefCmdSN必须是任务管理请求本身的查询任务（即，CmdSN和RefCmdSN相等）。
For a QUERY TASK of a task created by non-immediate command RefCmdSN MUST be set to the CmdSN of the task identified by the Referenced Task Tag field. Targets must use this field as described in section 11.6.1 of [RFC7143] when the task identified by the Referenced Task Tag field is not in the task set.
对于由非即时命令RefCmdSN创建的任务的查询任务，必须将RefCmdSN设置为由引用的任务标记字段标识的任务的CmdSN。当引用的任务标记字段标识的任务不在任务集中时，目标必须使用[RFC7143]第11.6.1节所述的该字段。
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|.| 0x22 |1| Reserved | Response | Reserved |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+-----------------------------------------------+---------------+
8| Additional Response Information | Reserved |
+-----------------------------------------------+---------------+
12| Reserved |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20| Reserved |
+---------------+---------------+---------------+---------------+
24| StatSN |
+---------------+---------------+---------------+---------------+
28| ExpCmdSN |
+---------------+---------------+---------------+---------------+
32| MaxCmdSN |
+---------------+---------------+---------------+---------------+
36/ Reserved /
+/ /
+---------------+---------------+---------------+---------------+
48| Header-Digest (Optional) |
+---------------+---------------+---------------+---------------+
Byte/ 0 | 1 | 2 | 3 |
/ | | | |
|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|0 1 2 3 4 5 6 7|
+---------------+---------------+---------------+---------------+
0|.|.| 0x22 |1| Reserved | Response | Reserved |
+---------------+---------------+---------------+---------------+
4|TotalAHSLength | DataSegmentLength |
+-----------------------------------------------+---------------+
8| Additional Response Information | Reserved |
+-----------------------------------------------+---------------+
12| Reserved |
+---------------+---------------+---------------+---------------+
16| Initiator Task Tag |
+---------------+---------------+---------------+---------------+
20| Reserved |
+---------------+---------------+---------------+---------------+
24| StatSN |
+---------------+---------------+---------------+---------------+
28| ExpCmdSN |
+---------------+---------------+---------------+---------------+
32| MaxCmdSN |
+---------------+---------------+---------------+---------------+
36/ Reserved /
+/ /
+---------------+---------------+---------------+---------------+
48| Header-Digest (Optional) |
+---------------+---------------+---------------+---------------+
Section 11.6 of [RFC7143] defines the semantics used for responses to SCSI task management functions. The following responses are defined in [RFC7143]:
[RFC7143]的第11.6节定义了用于响应SCSI任务管理功能的语义。[RFC7143]中定义了以下响应：
0 - Function Complete 1 - Task does not exist 2 - LUN does not exist 3 - Task still allegiant 4 - Task allegiance reassignment not supported 5 - Task management function not supported 6 - Function authorization failed 255 - Function rejected
0-功能完成1-任务不存在2-LUN不存在3-任务仍然保持一致4-任务一致性重新分配不受支持5-任务管理功能不受支持6-功能授权失败255-功能被拒绝
The Task Management Function Response PDU above and the list of task management function responses above are duplicated from [RFC7143] for reference only. [RFC7143] supersedes the text in section 6.4.1 of this document in the event the two documents conflict.
上述任务管理功能响应PDU和上述任务管理功能响应列表从[RFC7143]复制，仅供参考。[RFC7143]在两个文件发生冲突时，将取代本文件第6.4.1节中的文本。
Responses to new task management functions (see Section 6.4.2) are listed below. In addition, a new task Management response is listed below. For a more detailed description of SCSI task management responses, see [SAM5].
以下列出了对新任务管理功能（见第6.4.2节）的响应。此外，下面列出了一个新的任务管理响应。有关SCSI任务管理响应的更详细说明，请参阅[SAM5]。
For the functions QUERY TASK, QUERY TASK SET, I_T NEXUS RESET, and QUERY ASYNCHRONOUS EVENT, the target performs the requested Task Management function and sends a Task Management response back to the initiator.
对于函数QUERY TASK、QUERY TASK SET、I_T NEXUS RESET和QUERY ASYNCHRONOUS EVENT，目标执行请求的任务管理函数，并将任务管理响应发送回启动器。
The new response is listed below:
新的答复如下：
7 - Function succeeded
7-功能成功
In symbolic terms Response value 7 maps to the SCSI service response of FUNCTION SUCCEEDED in [SAM5].
用符号表示，响应值7映射到[SAM5]中成功的函数的SCSI服务响应。
The Task Management Function Response of "Function succeeded" MUST be supported by an initiator that sends any of the new task management functions (see Section 6.3).
发送任何新任务管理功能的启动器必须支持“功能成功”的任务管理功能响应（见第6.3节）。
For the QUERY TASK function, if the specified task is in the task set, then the logical unit returns a Response value of "Function succeeded", and additional response information is returned as specified in [SAM5]. If the specified task is not in the task set, then the logical unit returns a Response value of "Function complete".
对于查询任务函数，如果指定的任务在任务集中，则逻辑单元返回“函数成功”的响应值，并按照[SAM5]中的规定返回其他响应信息。如果指定的任务不在任务集中，则逻辑单元返回“函数完成”的响应值。
For the QUERY TASK SET function, if there is any command present in the task set from the specified I_T_L nexus, then the logical unit returns a Response value of "Function succeeded". If there are no commands present in the task set from the specified I_T_L nexus, then the logical unit returns a Response value of "Function complete".
对于查询任务集函数，如果任务集中存在来自指定I_T_L nexus的任何命令，则逻辑单元返回“函数成功”的响应值。如果指定I_T_L nexus的任务集中没有任何命令，则逻辑单元返回一个响应值“Function complete”。
For the I_T NEXUS RESET function, after completion of the events described in Section 6.3 for this function, the logical unit returns a Response value of "Function complete". However, because the target drops all connections, the Service Response (defined by [SAM5]) for this SCSI task management function may not be reliably delivered to the issuing initiator port.
对于I_T NEXUS RESET功能，在完成第6.3节中描述的该功能的事件后，逻辑单元返回“功能完成”的响应值。但是，由于目标会断开所有连接，因此此SCSI任务管理功能的服务响应（由[SAM5]定义）可能无法可靠地传递到发出的启动器端口。
For the QUERY ASYNCHRONOUS EVENT, if there is a unit attention condition or deferred error pending for the specified I_T_L nexus, then the logical unit returns a Response value of "Function succeeded", and additional response information is returned as specified in [SAM5]. If there is no unit attention or deferred error pending for the specified I_T_L nexus, then the logical unit returns a Response value of "Function complete".
对于查询异步事件，如果指定的I_T_L nexus存在单元注意条件或延迟错误挂起，则逻辑单元返回响应值“Function successed”，并按照[SAM5]中的规定返回其他响应信息。如果指定的I_T_L nexus没有单元注意或延迟错误挂起，则逻辑单元返回一个响应值“Function complete”。
Section 4.1 of [RFC5048] defines the notion of "affected tasks" in multi-task abort scenarios. This section adds to the list included in that section by defining the tasks affected by the I_T NEXUS RESET function.
[RFC5048]第4.1节定义了多任务中止场景中“受影响任务”的概念。本节通过定义受I_T NEXUS RESET功能影响的任务，将其添加到该节中包含的列表中。
I_T NEXUS RESET: All outstanding tasks received on the I_T nexus on which the function request was received for all logical units accessible to the I_T nexus.
I_T NEXUS RESET：I_T NEXUS上接收到的所有未完成任务，I_T NEXUS可访问的所有逻辑单元在其上接收到功能请求。
Sections 4.1.2 and 4.1.3 of [RFC5048] identify semantics for task management functions that involve multi-task abort operations. If an iSCSI implementation supports the I_T NEXUS RESET function, it MUST also support the protocol behavior as defined in those sections and follow the sequence of actions as described in those sections when processing the I_T NEXUS RESET function.
[RFC5048]第4.1.2节和第4.1.3节确定了涉及多任务中止操作的任务管理功能的语义。如果iSCSI实现支持I_T NEXUS重置功能，它还必须支持这些部分中定义的协议行为，并在处理I_T NEXUS重置功能时遵循这些部分中描述的操作顺序。
Use: LO, IO Irrelevant when: SessionType = Discovery Senders: Initiator and Target Scope: SW
当：SessionType=Discovery Senders:Initiator和目标作用域：SW时使用：LO，IO无关
iSCSIProtocolLevel=<numerical-value-from-0-to-31>
iSCSIProtocolLevel=<numerical-value-from-0-to-31>
Default is 1. Result function is Minimum.
默认值为1。结果函数是最小的。
This key is used to negotiate the use of iSCSI features that require different levels of protocol support (e.g., PDU formats, end-node semantics) for proper operation.
此密钥用于协商iSCSI功能的使用，这些功能需要不同级别的协议支持（例如PDU格式、端节点语义）才能正常运行。
Negotiation of the iSCSIProtocolLevel key to a value corresponding to an RFC indicates that both negotiating parties are compliant to the RFC in question and agree to support the corresponding PDU formats and semantics on that iSCSI session. Features using this key are expected to be cumulative.
将iSCSIProtocolLevel密钥协商为与RFC对应的值表示协商双方都遵守相关RFC，并同意在该iSCSI会话上支持相应的PDU格式和语义。使用此键的功能预计是累积的。
An iSCSIProtocolLevel key negotiated to "0" indicates that the implementation does not claim a specific iSCSI protocol level.
协商为“0”的iSCSIProtocolLevel密钥表示实现没有声明特定的iSCSI协议级别。
An iSCSIProtocolLevel key negotiated to "1" indicates that the implementation claims compliance with [RFC7143].
协商为“1”的iSCSIProtocolLevel密钥表示实现声明符合[RFC7143]。
An iSCSIProtocolLevel key negotiated to "2" is required to enable use of features defined in this RFC.
需要协商为“2”的iSCSIProtocolLevel密钥才能使用本RFC中定义的功能。
If the negotiation answer is ignored by the acceptor, or the answer from the remote iSCSI end point is key=NotUnderstood, then the features defined in this RFC, and the features defined in any RFC requiring a key value greater than "2", MUST NOT be used.
如果接受方忽略协商答案，或者来自远程iSCSI端点的答案为key=NotUnderstanding，则不得使用此RFC中定义的功能以及任何RFC中定义的需要大于“2”的键值的功能。
Command priorities are relative values, not absolute values (see [SAM5], and affect collections of commands, not necessarily individual commands (see [SAM5]). If command priority is supported, it should be implemented in a fashion that avoids unwanted reduction or denial of service.
命令优先级是相对值，而不是绝对值（参见[SAM5]），并影响命令集合，不一定影响单个命令（参见[SAM5]）。如果支持命令优先级，则应以避免不必要的减少或拒绝服务的方式实现。
All the iSCSI-related security text in [RFC3723] is directly applicable to this document. The security text in [RFC7143] is directly applicable as well.
[RFC3723]中所有与iSCSI相关的安全文本都直接适用于本文档。[RFC7143]中的安全文本也直接适用。
This document modifies or creates a number of iSCSI-related registries.
本文档修改或创建了许多与iSCSI相关的注册表。
The following iSCSI-related registries are modified.
修改了以下与iSCSI相关的注册表。
1. iSCSI Task Management Functions Codes
1. iSCSI任务管理功能代码
Name of the existing registry: "iSCSI Task Management Function Codes"
现有注册表的名称：“iSCSI任务管理功能代码”
The following entries have been added:
已添加以下条目：
9 - QUERY TASK, RFC 7144
9-查询任务，RFC 7144
10 - QUERY TASK SET, RFC 7144
10-查询任务集，RFC 7144
11 - I_T NEXUS RESET, RFC 7144
11-I_T NEXUS重置，RFC 7144
12 - QUERY ASYNCHRONOUS EVENT, RFC 7144
12-查询异步事件，RFC 7144
13-127 - Unassigned
13-127-未分配
2. iSCSI Login/Text Keys
2. iSCSI登录/文本密钥
Name of the existing registry: "iSCSI Login/Text Keys"
现有注册表的名称：“iSCSI登录/文本键”
Fields to record in the registry: Assigned value and its associated RFC reference.
要在注册表中记录的字段：赋值及其关联的RFC引用。
The following entry has been added:
已添加以下条目：
iSCSIProtocolLevel, RFC 7144
iSCSIProtocolLevel，RFC 7144
IANA has created the following iSCSI-related registries.
IANA已创建以下与iSCSI相关的注册表。
3. iSCSI Protocol Level
3. iSCSI协议级别
Name of new registry: "iSCSI Protocol Level"
新注册表的名称：“iSCSI协议级别”
Namespace details: Numerical values from 0 to 31
命名空间详细信息：0到31之间的数值
Information that must be provided to assign a new value: An IESG-approved Standards Track specification defining the semantics and interoperability requirements of the proposed new value and the fields to be recorded in the registry.
分配新值必须提供的信息：IESG批准的标准跟踪规范，定义了拟议新值的语义和互操作性要求以及要记录在注册表中的字段。
Assignment policy:
派遣政策：
The assignments of these values must be coordinated with the INCITS T10 committee; therefore, review by an expert that maintains an association with that committee is required prior to IESG approval of the associated specification. After creation of the registry, values are to be assigned sequentially (for example, any value greater than 4 will not be assigned until after the value 4 has been assigned).
这些值的分配必须与INCITS T10委员会协调；因此，在IESG批准相关规范之前，需要由与该委员会保持联系的专家进行审查。创建注册表后，将按顺序分配值（例如，在分配值4之前，不会分配任何大于4的值）。
Special care must be taken in the assignment of new values in this registry. Compatibility and interoperability will be adversely impacted if proper care is not exercised. Features using this key are expected to be cumulative. For example, since this document explicitly lists only value 2 for the features listed in this document, it is expected that a new RFC assigning value 3 will also have the features listed in this RFC, and therefore such an RFC is expected to either revise or replace this RFC. Assignments that do not follow this policy should be reviewed and approved by the INCITS T10 committee.
在此注册表中分配新值时必须特别小心。如果不采取适当的措施，兼容性和互操作性将受到不利影响。使用此键的功能预计是累积的。例如，由于本文档仅明确列出了本文档中列出的功能的值2，因此新的RFC赋值3也将包含本RFC中列出的功能，因此此类RFC将修订或替换本RFC。不符合本政策的作业应由INCITS T10委员会审查和批准。
3-31: range available to IANA for assignment in this registry.
3-31：IANA可在此注册表中分配的范围。
Fields to record in the registry: Assigned value, description, and its associated RFC reference.
要在注册表中记录的字段：赋值、说明及其关联的RFC引用。
The following entries have been added:
已添加以下条目：
Value Description Reference
值描述参考
0 No version claimed RFC 7144
0无版本声明RFC 7144
1 RFC 7143 [RFC7143]
1 RFC 7143[RFC7143]
2 RFC 7144 RFC 7144
2 RFC 7144 RFC 7144
3-31 Unassigned
3-31未分配
Allocation Policy: Expert Review and Standards Action [RFC5226]
分配政策：专家审查和标准行动[RFC5226]
4. iSCSI Task Management Function Response Codes
4. iSCSI任务管理功能响应代码
Name of new registry: "iSCSI Task Management Function Response Codes"
新注册表名称：“iSCSI任务管理功能响应代码”
Namespace details: Numerical values that can fit in 8 bits.
名称空间详细信息：可以容纳8位的数值。
Information that must be provided to assign a new value: An IESG-approved specification defining the semantics and interoperability requirements of the proposed new value and the fields to be recorded in the registry.
分配新值必须提供的信息：IESG批准的规范，该规范定义了拟议新值的语义和互操作性要求以及要记录在注册表中的字段。
Assignment policy:
派遣政策：
If the requested value is not already assigned, it may be assigned to the requester.
如果请求的值尚未分配，则可以将其分配给请求者。
8-254: Range available to IANA for assignment in this registry.
8-254：IANA可在此注册表中分配的范围。
Fields to record in the registry: Assigned value, Operation Name, and its associated RFC reference.
要在注册表中记录的字段：赋值、操作名称及其关联的RFC引用。
The following entries have been added:
已添加以下条目：
0 - Function complete, [RFC7143]
0-功能完成，[RFC7143]
1 - Task does not exist, [RFC7143]
1-任务不存在[RFC7143]
2 - LUN does not exist, [RFC7143]
2-LUN不存在[RFC7143]
3 - Task still allegiant, [RFC7143]
3-任务仍然是allegiant[RFC7143]
4 - Task allegiance reassignment not supported, [RFC7143]
4-不支持任务忠诚重新分配[RFC7143]
5 - Task management function not supported, [RFC7143]
5-不支持任务管理功能[RFC7143]
6 - Function authorization failed, [RFC7143]
6-功能授权失败，[RFC7143]
7 - Function succeeded, RFC 7144
7-功能成功，RFC 7144
8-254 - Unassigned
8-254-未分配
255 - Function rejected, [RFC7143]
255-函数被拒绝[RFC7143]
Allocation Policy: Standards Action [RFC5226]
分配政策：标准行动[RFC5226]
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2119]Bradner，S.，“RFC中用于表示需求水平的关键词”，BCP 14，RFC 2119，1997年3月。
[RFC3723] Aboba, B., Tseng, J., Walker, J., Rangan, V., and F. Travostino, "Securing Block Storage Protocols over IP", RFC 3723, April 2004.
[RFC3723]Aboba，B.，Tseng，J.，Walker，J.，Rangan，V.，和F.Travostino，“通过IP保护块存储协议”，RFC 37232004年4月。
[RFC5048] Chadalapaka, M., Ed., "Internet Small Computer System Interface (iSCSI) Corrections and Clarifications", RFC 5048, October 2007.
[RFC5048]Chadalapaka，M.，编辑，“互联网小型计算机系统接口（iSCSI）更正和澄清”，RFC 5048，2007年10月。
[RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an IANA Considerations Section in RFCs", BCP 26, RFC 5226, May 2008.
[RFC5226]Narten，T.和H.Alvestrand，“在RFCs中编写IANA注意事项部分的指南”，BCP 26，RFC 5226，2008年5月。
[RFC7143] Chadalapaka, M., Satran, J., Meth, K., and D. Black, "Internet Small Computer System Interface (iSCSI) Protocol (Consolidated)", RFC 7143, April 2014.
[RFC7143]Chadalapaka，M.，Satran，J.，Meth，K.，和D.Black，“互联网小型计算机系统接口（iSCSI）协议（整合）”，RFC 71432014年4月。
[SAM2] INCITS Technical Committee T10, "SCSI Architecture Model - 2 (SAM-2)", ANSI INCITS 366-2003, ISO/IEC 14776-412, 2003.
[SAM2]INCITS技术委员会T10，“SCSI体系结构模型-2（SAM-2）”，ANSI INCITS 366-2003，ISO/IEC 14776-4122003。
[SAM5] INCITS Technical Committee T10, "SCSI Architecture Model - 5 (SAM-5)", T10/BSR INCITS 515 rev 04, Committee Draft.
[SAM5]INCITS技术委员会T10，“SCSI架构模型-5（SAM-5）”，T10/BSR INCITS 515版本04，委员会草案。
[SPC4] INCITS Technical Committee T10, "SCSI Primary Commands - 4", ANSI INCITS 513-201x.
[SPC4]INCITS技术委员会T10，“SCSI主要命令-4”，ANSI INCITS 513-201x。
[RFC3720] Satran, J., Meth, K., Sapuntzakis, C., Chadalapaka, M., and E. Zeidner, "Internet Small Computer Systems Interface (iSCSI)", RFC 3720, April 2004.
[RFC3720]Satran，J.，Meth，K.，Sapuntzakis，C.，Chadalapaka，M.，和E.Zeidner，“互联网小型计算机系统接口（iSCSI）”，RFC 3720，2004年4月。
The Storage Maintenance (STORM) Working Group in the Transport Area of the IETF has been responsible for defining these additions to the iSCSI protocol (apart from other relevant IP Storage protocols). The authors acknowledge the contributions of the entire working group and other IETF reviewers.
IETF传输领域的存储维护（STORM）工作组负责定义iSCSI协议的这些新增内容（除其他相关IP存储协议外）。作者感谢整个工作组和其他IETF评审员的贡献。
The following individuals directly contributed to identifying issues and/or suggesting resolutions to the issues clarified in this document: David Black, Rob Elliott. This document benefited from all of these contributions.
以下个人直接参与确定问题和/或建议解决本文件中澄清的问题：David Black，Rob Elliott。本文件得益于所有这些贡献。
Authors' Addresses
作者地址
Frederick Knight 7301 Kit Creek Road P.O. Box 13917 Research Triangle Park, NC 27709 USA
Frederick Knight 7301 Kit Creek路美国北卡罗来纳州三角研究公园13917号邮政信箱27709
Phone: +1-919-476-5362
EMail: knight@netapp.com
Phone: +1-919-476-5362
EMail: knight@netapp.com
Mallikarjun Chadalapaka Microsoft One Microsoft Way Redmond, WA 98052 USA
Mallikarjun Chadalapaka Microsoft One Microsoft Way Redmond，WA 98052美国
EMail: cbm@chadalapaka.com
EMail: cbm@chadalapaka.com