Heya folks, Ned here again. A customer contacted us about a strange behavior they were seeing when copying large files to a Windows Server 2019 cluster using SMB 3.1.1. Around every 5GB transferred, ...
Updated Nov 07, 2022
Version 3.0
Blog Post
The described behavior of large file copying pausing every 5GB transferred on a Windows Server 2019 cluster using SMB 3.1.1 could be due to several factors:
1. **SMB Configuration**: Check the SMB configuration settings on the Windows Server 2019 cluster to ensure optimal performance. Adjustments may be needed to optimize settings such as MaxBufferSize, MaxCredits, and EnableLargeMtu.
2. **Network Congestion**: Analyze network traffic and identify any bottlenecks or congestion points that may be causing the pauses during file transfers. This could involve examining network switch configurations, bandwidth utilization, and latency.
3. **Storage Configuration**: Evaluate the storage configuration, including Storage Spaces Direct and disk layout, to ensure it is optimized for high-performance file transfers. Check for any disk latency issues or RAID configurations that may be affecting performance.
4. **Antivirus and Filter Drivers**: Disable or temporarily uninstall antivirus software and any third-party filter drivers to see if they are causing the pauses during file transfers. Sometimes, these security measures can introduce unexpected delays.
5. **Windows Server 2019 Specific Issues**: Investigate if there are any known issues or hotfixes related to SMB file transfers on Windows Server 2019 that could be causing the behavior. Microsoft's support website and forums may provide insights into any reported issues and potential resolutions.
6. **Comparative Analysis with Windows Server 2012 R2**: Since the issue does not occur when copying to a Windows Server 2012 R2 destination, perform a comparative analysis of the SMB configurations, network settings, and storage configurations between the two environments to identify any differences that may be contributing to the behavior.
By systematically troubleshooting and addressing these potential factors, it should be possible to diagnose and resolve the issue with large file copying on the Windows Server 2019 cluster.