So, yesterday I upgraded my Raspberry Pi from Raspbian Jessie to Stretch using this helpful post on the Raspberry Pi site. Everything went smoothly, except my Sonos couldn’t connect afterwards. This is a critical issue in our household, as the Pi hosts our brown noise mp3. Everything worked before the upgrade, and I could connect from my Mac to the SMB share. But Sonos refused. What gives?
Sonos uses the older NTLM authentication scheme to connect to SMB shares. The version of Samba that comes in Debian Stretch has that disabled by default. The fix was to add the following to the smb.conf file:
[global] ntlm auth=yes
After this addition, Sonos was once again able to connect to the share, and the entire family was able to sleep like logs after a long day.