Mac OS X Server 10.2.8 or Earlier: How to Prevent One File From Being Simultaneously Modified by Two Users

Symptom

An Apple File Services (AFP) client is able to obtain read-write access to a file that is already being modified by a Windows File Service (SMB) or NFS client, or vice versa.

Note: It would normally be expected that secondary users of a file get read-only access.


Solution

File locking systems vary between Apple Filing Protocol, SMB, and NFS. Use the following strategies to avoid the issue.

Using AFP with SMB

When sharing simultaneously via AFP and SMB, take these actions:

1. Be sure that client and server are both updated to version 10.2.3 or later.
2. When configuring Windows File Settings for a share point in Workgroup Manager, be sure the checkbox for "Enable strict locking" is selected.

Note: If you cannot immediately update to 10.2.3 or later, use only one protocol per share point.

Using NFS

To prevent this issue when using NFS, separate your share points by protocol. Use one share point for NFS clients, and another share point for AFP and SMB clients.

Note: All versions of Mac OS X can connect to a server over NFS. Mac OS X 10.1 or later can connect to file servers over SMB.