[Samba] server max protocol appropriate values

Gaiseric Vandal gaiseric.vandal at gmail.com
Wed Mar 4 13:55:20 MST 2015

I have several Samba 3.6.24  domain controllers/file servers .

Server1 -   Solaris 10, Samba 3.6.24, max protocol NT1.     This is the 
main file server.
Server2 -   Solaris 10, Samba 3.6.24, max protocol SMB2.   2ndary file 
server, not as heavily used as as server1.
Server3 -   Solaris 11, Samba 3.6.24, max protocol SMB2 .   This was set 
up to replace Server 1.

I also have a a Citrix XenApp 6.5 server running on Windows 2008 R2 with 
RDP/Terminal Services role

On do of them, I changed the server max protocol from NT1 to SMB2, with 
no problem - at first. I  was  migrating data from server1 to 
server3.      As I moved data over from , people started having trouble 
with being able to establish connections to the new server from the 
citrix server.    Windows 7 clients were fine (except for a single 
problem on a single Win 7 laptop.)   It really pointed to something 
specific with a Citrix server environment.   I think it has something to 
do with SMB2 establishing separate connections for each user and 
exceeding the default number of permitted sessions on Win 2008.          
Rolling back to NT1 seemed to fix it the issues.

On 03/04/15 10:26, James wrote:
> Hello,
>      My DC smb.conf currently has the following set
>          server max protocol = NT1
>          server min protocol = CORE
>          client max protocol = NT1
>          client min protocol = CORE
> Is it safe to change both the client and server max to = SMB3? What
> about on member servers? Should I be concerned with anything breaking?
> I'm using Windows 7 clients to authenticate against Ubuntu 4.1.17 DC's
> and a Debian Wheezy as a file server.
> This is what I see on
> https://www.samba.org/samba/docs/man/manpages-3/smb.conf.5.html
> Normally this option should not be set as the automatic negotiation
> phase in the SMB protocol takes care of choosing the appropriate protocol.
> Default: //|server max protocol|/ = |SMB3| /
> Example: //|server max protocol|/ = |LANMAN1| /

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