What is SMB Oplock?

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Opportunistic locks, or oplocks, provide a mechanism that allows file server clients (such as those utilizing the SMB and SMB2 protocols) to dynamically alter buffering strategy for a given file or stream in a consistent manner to increase performance and to reduce network use.

Should I disable opportunistic locking?

Using the embedded database on Windows networks without disabling oplocks is not recommended or supported and has a high likelihood of data corruption. Disabling oplocks may have a performance impact on Windows networks.

What is CIFS Oplocks?

CIFS oplocks enable the redirector on a CIFS client in certain file-sharing scenarios to perform client-side caching of read-ahead, write-behind, and lock information. A client can then work with a file (read or write it) without regularly reminding the server that it needs access to the file.

How do I disable Oplock?

To Disable SMB2 and OPLOCK (Network Locking Errors)

Click Start, type regedit in the Start Search box.
Locate and then click the following registry subkey:
On the Edit menu, point to New, and then click DWORD Value.
Type SMB2, and then press ENTER.
On the Edit menu, click Modify.
Type 0 (zero), and then click OK.

What are SMB durable handles?

Durable handles allow SMB 2.0 clients to open a file and survive a temporary connection loss. A durable handle is an open file handle that is preserved during a short network outage, which allows a client to reconnect when connectivity is restored.

Should you disable SMBv2?

We recommend keeping SMBv2 and SMBv3 enabled, but you might find it useful to disable one temporarily for troubleshooting. For more information, see How to detect status, enable, and disable SMB protocols on the SMB Server.

What is Oplocks netapp?

Oplocks let clients lock files and locally cache information while preventing another user from changing the file. This increases performance for many file operations.

What is SMB service Synology?

SMB Service is an easy-to-use file service management tool, allowing you to manage general settings related to the SMB/CIFS file sharing service. Through SMB Service, Windows, macOS, and Linux users can access your Synology NAS from the network once you have enabled the SMB service option in Control Panel.

What happens if you disable SMB?

Warning. Disabling SMBv1 without thoroughly testing for SMBv1 traffic in your environment can have unintended consequences, up to and including a complete suspension of all network services, denied access to all resources, and remote authentication failures (like LDAP).