The smb-protocols nmap script checks to see which smb dialects are present on the Samba server.
client min protocol sets the minimum smb dialect that server can use to connect to another server not the minimum dialects that a client to this server can use.
By default the version of samba used in Ubuntu 18.04 sets the server min to NT1 ( smbv1 ) and the max to SMBv3.
If you want to restrict access to this server to SMB3 and SMB3 only you need to set the server min protocol:
server min protocol = SMB3
*Note: there are sub-variants to this dialect:
SMB3_00: Windows 8
SMB3_02: Windows 8.1
SMB3_10: early Windows 10
SMB3_11: Windows 10
By default SMB3 in smb.conf selects the SMB3_11 variant.*
Answer from Morbius1 on askubuntu.com
There are multiple SMB protocol versions that can be set used, by editing /etc/samba/smb.conf
[global]
min protocol = SMB2I can set a minimum, and maximum version for my system. However, this could leave a range of versions that are actually used.
Is it possible to set a preferred version, which is used if both the client and server support this version?
Or is there a way to get SMB to use the latest compatible version, not the minimum (seeing as it defaults to version 1.0)?
The issue here is very simple, Network browsing is using SMBv1!!! In the latest SNIA SDC Microsoft announced about the death of SMBv1(disable by default - register) but still the network browsing will work over SMBv1.
That is why you could not see your device.
Try to modify only the server : server min protocol = SMB2_10
And leave the Client to support SMBv1
Run secpol.msc
I had to disable this here to get mine to work.
The smpd version 3.6.x doesn't support SMB3, so it won't recognize it. Using max protocol = SMB2 should enable the SMB2 support, so start with it. If you then add min protocol = SMB2 the list gets quite narrow...
The LTS support for Debian 7 "Wheezy" ends on May 31, 2018. That's in less than a week. Upgraded Debian 9 comes with smbd 4.5.x, and SMB 3.0 is supported since smbd 4.2. It will support your max protocol = SMB3.
@Esa Jokinen already answer you, and I think his answer will solve your issue.
Let me give some more details, Here is a link for the explanation on how and what should you do for enable the SMB2 on your Samba (3.6.x). (look for "SMB2 support")
In generally just do the following:
- In the
smb.conf[global] section addmax protocol = SMB2 - Restart your Samba.
My testing with Nessus has indicated SMBv1 is only disabled when setting
min protocol = SMB2
in the [global] section of smb.conf . Core, LANMAN2 and NT1 were all still flagged as being vulnerable.
I had to add this for it to work in my old ubuntu 12-server; with either of min/max-combination SMBv1 is enabled but with both it works fine.
[global]
min protocol = SMB2
max protocol = SMB2
client min protocol = SMB2
client max protocol = SMB2