We’ve had an unusual amount of clients dropping SMB connections throughout the day. Issues include directory contents suddenly disappearing while the user is browsing in Finder, ridiculously slow file transfer speeds, and files/folders mysteriously restricting user access.
Until Apple fixes this, we’ve found that making changes to the nsmb.conf file found at /etc/nsmb.conf can make a world of difference. I’ve added the following configuration to our fleet and have already seen improvements:
[default] minauth=ntlmv2 port445=normal streams=yes soft=yes signing_required=no submounts_off=yes
The help file for this configuration is found at man nsmb.conf. Performance increases greatly when turning off signing_required. Submounts are turned off as users sometimes email each other with direct links to file server resources. These start with smb:// and include the entire file path. This often results with multiple mount points on their desktop for the same file server. Turning that off stops them from mounting it again under a different name/source folder.