From the man page for the configuration file for the Samba suite in the "client max protocol" section:
Possible values are :
- CORE: Earliest version. No concept of user names.
- COREPLUS: Slight improvements on CORE for efficiency.
- LANMAN1: First modern version of the protocol. Long filename support.
- LANMAN2: Updates to Lanman1 protocol.
- NT1: Current up to date version of the protocol. Used by Windows NT. Known as CIFS.
- SMB2: Re-implementation of the SMB protocol. Used by Windows Vista and later versions of Windows. SMB2 has sub protocols available.
- SMB2_02: The earliest SMB2 version.
- SMB2_10: Windows 7 SMB2 version.
- SMB2_22: Early Windows 8 SMB2 version.
- SMB2_24: Windows 8 beta SMB2 version.
By default SMB2 selects the SMB2_10 variant.
- SMB3: The same as SMB2. Used by Windows 8. SMB3 has sub protocols available.
- SMB3_00: Windows 8 SMB3 version. (mostly the same as SMB2_24)
- SMB3_02: Windows 8.1 SMB3 version.
- SMB3_10: early Windows 10 technical preview SMB3 version.
- SMB3_11: Windows 10 technical preview SMB3 version (maybe final).
By default SMB3 selects the SMB3_11 variant.
Normally this option should not be set as the automatic negotiation phase in the SMB protocol takes care of choosing the appropriate protocol.
The value default refers to SMB3_11.
Adding clarification from A.B in the comments:
Answer from Jeff Schaller on Stack Exchangewiki.samba.org/index.php/Samba3/SMB2 states "Samba 3.6 added basic support for SMB2.0", "Basic support for SMB 2.1 was added in Samba 4.0.0", "Basic support for SMB3 is included in Samba 4.0.0 and later."
networking - Set SMB2 protocol in Samba 3.6.6 - Unix & Linux Stack Exchange
[Question] Set preferred samba protocol version
Samba SMB2 config not taking effect
debian - smb.conf min protocol = SMB2 timeouts from remote (local network) machine - Unix & Linux Stack Exchange
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
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.
SLES 11.4 is old enough for its Samba to default to SMBv1 only. You've set both client min protocol and client max protocol, which only affect Samba when it's acting as a client, like smbclient.
For server-side, you've only set server min protocol, so the server max protocol is still defaulting to SMBv1. And because now min protocol is higher than max, smbd actually cannot allow any protocol at all.
The facts that SLES 11.4's Samba is so old and its SMBv3 support seems to be buggy (as you discovered) caused us to make it a priority at work to upgrade any Samba servers that were still running SLES 11.4 to SLES 12 or newer.
running Samba-3.6.3 in SLES 11.4 which has kernel 3.0, my global section is this and I know SMB2 works because windows 10 client will NOT connect via SMB1 the minimum is SMB2 for win10 out of the box.
Note that if you set Min Protocol = SMB2 then if your clients are Windows 7 it will not work for them... at least i did not figure it out troubleshooting on the windows side I think for Win7 it is default SMB1 unless you manually configure something in win7 to say do SMB2.
And for whatever reason setting max protocol = SMB3 caused things not to work for me thus I have SMB2 specified.
[global]
min protocol = SMB2
max protocol = SMB2
workgroup = workgroup
passdb backend = tdbsam
map to guest = Never
usershare allow guests = No
add machine script = /usr/sbin/useradd -c Machine -d /var/lib/nobody -s /bin/false %m$
domain master = No
security = user
wins support = No
server signing = auto
name resolve order = lmhosts bcast host
printing = bsd
printcap name = /dev/null
log level = 2 auth:10 auth_audit:3 auth_json_audit:3 winbind:5
max log size = 1000000
and a sample of a share that i use
[data1]
create mask = 660
directory mask = 770
inherit acls = Yes
path = /data1
read only = No
you should not need to do anything in /etc/fstab other than mounting your storage resource as you normally would. Then once mounted make sure access permissions of that folder... chmod 777 /data1 in my example, are open for starters, then when working go ahead and remove world permissions and change group ownership and permissions as you need.
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)?
After a lot of experimentation, in ubuntu 16.04.x this is the solution. Works with Thunar, Nautilus, pcmanfm, Dolphin file managers.
The fix suggested of setting "client max protocol = SMB3_10" in /etc/samba/smb.conf also fixed the problem for me. [1]
Do this in the client ubuntu machine, in addition to the server. This might sound weird but works. [2]
The current Samba version in Ubuntu 16.04 defaults to making NT1 (SMB1) connections even though it supports SMB2 and SMB3 - hence it works when you specify the client version from the command line. The default is scheduled to change to SMB3 in Samba 4.7 (due for release soon) and already does this in LE because we backported the change to Samba 4.6 for our codebase. You have two options:
a) Configure the system smb.conf in Ubuntu to have "client min protocol = smb2" and "client max protocol = smb3" so that smbclient connections are forced to use something higher than NT1 .. then you don't need to specify the protocol version manually.
From debian bug report https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=883939
https://forum.libreelec.tv/thread/9920-solved-8-1-1-samba-access-from-linux-protocol-negotiation-failed/
min protocol = SMB2
NOT
client min protocol = SMB3
Got an extra word in there.