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2.2.24.1 Oplock Break Acknowledgment

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 The Oplock Break Acknowledgment packet is sent by the client in response to an SMB2 Oplock Break Notification packet sent by the server. The server responds to an oplock break acknowledgment with an SMB2 Oplock Break response. A break from level II MUST transition to none. Thus, the client does not send a request to the server because there is no question how the transition was made. This message is composed of an SMB2 header, as specified in section 2.2.1, followed by this acknowledgement structure.


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StructureSize

OplockLevel

Reserved

Reserved2

FileId

...

...

...

StructureSize (2 bytes): The client MUST set this to 24, indicating the size of the request structure, not including the header.

OplockLevel (1 byte):  The client will set this field to the lowered oplock level that the client accepts for this file. This field MUST contain one of the following values.

Value

Meaning

SMB2_OPLOCK_LEVEL_NONE

0x00

The client has lowered its oplock level for this file to none.

SMB2_OPLOCK_LEVEL_II

0x01

The client has lowered its oplock level for this file to level II.

SMB2_OPLOCK_LEVEL_EXCLUSIVE

0x08

The client has lowered its oplock level for this file to level Exclusive.

Reserved (1 byte): This field MUST NOT be used and MUST be reserved. The client MUST set this to 0, and the server MUST ignore it on receipt.

Reserved2 (4 bytes): This field MUST NOT be used and MUST be reserved. The client MUST set this to 0, and the server MUST ignore it on receipt.

FileId (16 bytes): An SMB2_FILEID, as specified in section 2.2.14.1.

The identifier of the file or pipe on which the oplock break occurred.