Samba Slow – Oplock break failed for file

Oplock break failed – Slow copying of files in Samba

If you are facing sluggishness in copying files to your samba drive, there is a good chance that, it may be because the error “Oplock break failed for file” in your /var/log/syslog(Ubuntu) and /var/log/messages(In other linux distributions)

Jan 07 11:31:27 machinename smbd[3641]: Oplock break failed for file filename.txt

To resolve this, you may need to add the below entries to the [global] section of your smb.conf(/etc/samba/smb.conf)

[global]
.......
.......
kernel oplocks = no
nt acl support = no
strict locking = no

Then add the below entries under [your share name] section of smb.conf

[your share name]
........
........
oplocks = no
share modes = no
locking = no
acl check permissions = false
level2 oplocks = no
strict locking = no
blocking locks = no