2025-12-28
Sometimes Time Machine runs into repeated problems over SMB wifi that result in “this backup needs to be restarted”, or somehow is no longer able to successfully conclude a backup. I had the issue where the first backup would always work but 9 out of 10 subsequent backups would fail with “network disk disconnected during backup”, especially when backing up to Synology Disk Stations.
After years of struggling, I finally found the key settings to change on the Synology. These are the settings that made my issues go away:
In “File Protocols => SMB Advanced Settings” set (loose translations from my German system):
| Function | Setting |
|---|---|
| Maximum SMB protocol | SMB3 |
| Minimum SMB protocol | SMB2 and Large MTU |
| Encryption mode | Enforce |
| Serv… |
2025-12-28
Sometimes Time Machine runs into repeated problems over SMB wifi that result in “this backup needs to be restarted”, or somehow is no longer able to successfully conclude a backup. I had the issue where the first backup would always work but 9 out of 10 subsequent backups would fail with “network disk disconnected during backup”, especially when backing up to Synology Disk Stations.
After years of struggling, I finally found the key settings to change on the Synology. These are the settings that made my issues go away:
In “File Protocols => SMB Advanced Settings” set (loose translations from my German system):
| Function | Setting |
|---|---|
| Maximum SMB protocol | SMB3 |
| Minimum SMB protocol | SMB2 and Large MTU |
| Encryption mode | Enforce |
| Server signing | Client-defined |
| Opportunistic locking | Active |
| SMB2 lease | Active |
| SMB permanent handles | Active |
Try these settings and may your Time Machine backups successfully complete over wifi to your Synology and no longer fail with “network disk disappeared” or similar.