Add "client min protocol = NT1" to /etc/samba/smb.conf in [global] section

It is required to access NAS which only support SMB v1 with the new Samba v4.11.6 included in Ubuntu 20.04. Samba 4.11.x disables by default SMB v1.

You will probably need the fix for this bug to be published in main Ubuntu repository, as pointed by Opifex.

Answer from Bruno on askubuntu.com
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networking - Samba on Ubuntu 20.04 stopped working after todays update: more info - Ask Ubuntu
December 15, 2021 - Check smbd. smbd --version Version 4.13.14-Ubuntu Below smb.conf was working prior to today's update. from: sudo nano /etc/samba/smb.conf towards top of file: # Change this to the workgroup/NT-do...
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software installation - Cannot install Samba client on Ubuntu 20.04 - Unix & Linux Stack Exchange
Bring the best of human thought ... at your work. Explore Stack Internal ... I just upgraded my Ubuntu from 18.04 to 20.04. Now I lost my access to my NAS and I am trying to re-install it. I read several posts about the issue that others had when upgrading, including the fact that the new Samba doesn't support SMB V 1.0 and how to fix it. I found that Samba client is not installed ... More on unix.stackexchange.com
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fresh install of Ubuntu 20.04.5 installed samba mac seeing network, but not seeing any folders
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February 8, 2023
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1 of 7
49

Same issue here.

Since version 4, both Samba Server & Samba Clients do not allow an older level of protocols negotiation. You have to enable them in smb.conf file

Edit /etc/samba/smb.conf file (need root permissions)

in the [global] section, add the following line

client min protocol = NT1

Save the file and exit the editor.

You must restart the Samba Service for this change to take effect. In a terminal, enter this command:

sudo service smbd restart

You should be able to access your samba shares successfully. If you cannot connect to your samba share, you can lower even more the protocol security in smb.conf (not recommended), by using:

client min protocol = CORE

Cheers!

2 of 7
6

Same issue here. It worked out of the box in 18 and 19 without any further step. It's easy to check with a 18,19 live dvd. In a february discussion, they wondered if this out of the box feature should be scraped in 20.04.

Samba.libs and samba.common are installed by default in 18,19, 20.04 but it does not work in the latter Simply installing the full Samba package, which installs /etc/samba/smb.conf. and adding under [GLOBAL] client min protocol = NT1 or CORE does not work. You can access the NAS folder but every object text, jpg etc. is treated as a folder.

There is a bug report relating to NAS and samba. https://bugs.launchpad.net/ubuntu/+source/samba/+bug/1872476 If you install full samba add NT1 to smb.conf (installed by full samba), you can access the NAS share but all objects in the share (avi, jp, txt, etc.) are seen as folders.

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software installation - Cannot install Samba client on Ubuntu 20.04 - Unix & Linux Stack Exchange
The following information may help to resolve the situation: The following packages have unmet dependencies. samba : Depends: python3-samba but it is not going to be installed Depends: samba-common-bin (= 2:4.11.6+dfsg-0ubuntu1.5) but it is not going to be installed Depends: libldb2 (>= 2:2.0.10~) but it is not going to be installed Depends: libpython3.8 (>= 3.8.2) but it is not going to be installed Depends: libwbclient0 (= 2:4.11.6+dfsg-0ubuntu1.5) but 2:4.7.6+dfsg~ubuntu-0ubuntu2.20 is to be installed Depends: samba-libs (= 2:4.11.6+dfsg-0ubuntu1.5) but 2:4.7.6+dfsg~ubuntu-0ubuntu2.20 is to
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samba - Windows share smb connection hangs on Ubuntu 20.04 - Stack Overflow
After upgrading to Ubuntu 20.04, however, on the step 4 (after I enter my credentials and try to connect) the connection just hangs, and the shared network is not mounted. After researching the problem a bit, the potential solutions I found did not work, most of which suggests to add the following to smb.conf to be able to access to SMB1 type of network.
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1 of 3
1

I found my issue was the samba client (as I don't have samba server running at all anywhere in my setup).

The desktop client (MATE Caja file manager) would see the NAS server with the wrong name. It would see the NAS box name (mynas) rather than the configured SMB server name (homebackup).

When I used :

$ smbclient //homebackup/mybackup

I was able to connect and browse and copy files via smbclient.

So I went into Caja and manually typed :

smb://homebackup/mybackup

And wala the share appeared.

So for me the only problem is browsing the network and not attaching to shares.

Even after manually connecting in this way the Caja browser still shows mynas instead of homebackup under networks!!!

2 of 3
0

Just for completeness...as I could not read the exact instructions from the posts. If you have a NAS (e.g. FritzBox) that uses SMB1 you can make nautilus/gio downgrade the smb connection with the following commands, if you don't already have a .smb/smb.conf file (like me):

mkdir ~/.smb
echo "[global]" > ~/.smb/smb.conf
echo "client min protocol = CORE" >> ~/.smb/smb.conf

As an alternative for FritzBox users you could possibly upgrade your FritzBox to SMB2/SMB3 using the experimental Fritz!Lab OS. See https://en.avm.de/service/fritzbox/fritzbox-7490/knowledge-base/publication/show/3327_SMB-versions-supported-by-the-FRITZ-Box/

Then you possibly don't need this workaround, but I didn't test that yet.

The bug with the files showing as folders is fixed now in Ubuntu 20.04 (focal) with smblibs package version 4.11.6+dfsg-0ubuntu1.2

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4

There are two issues here - really three - that have combined to cause the issue you reported.

One is a bug in gvfs ( gvfsd-smb-browse ) that is hard-wired to use SMB1 ( NT1 ) to get a list of the servers and their shares when you browse for them in your file manager.

The second one is Sambas decision to disable ( but not remove ) SMB1 on both the client and server side.

Your samba server can run between SMB2.02 to SMB3. The bug in gvfs causes the samba client to try to access that server using SMB1 which the server cannot understand so it throws an error:

Failed to retrieve share list from server: Invalid argument

There are three ways to get around this issue:

[1] Bypass gvfsd-smb-browse by asking for the server and its share in Connect to Server: smb://server-host-name.local/share-name

Samba client and server will connect using SMB3.

[2] OR do what you just did and set the min server and client to SMB1 ( NT1 ). IT will also connect using SMB3 because the server and client negotiate with one another to determine the best dialect to use after the initial SMB1 connection.

[3] OR use a mount.cifs mount which will also connect using SMB3. This has to be set up in fstab to happen automatically.

If it makes you feel any better a newly installed Win10 machine will not be able to "discover" your samba server at all because it too disabled SMB1. The solution there is the same as for your Linux system: Connect with a \\server-host-name.local OR enable SMB1 on the client side of Win10 which Microsoft really doesn't want anyone to do.

2 of 2
0

Same problem here. My windows machine were working fine with my local Samba server but my Ubuntu 20.04.4 machine could not. Usually in my Ubuntu file browser I would acces the server with :

smb://server-host-name.local/share-name

but it would not work.

The solution that works for me is replacing the server name by the IP adress of the server. Example:

smb://14.15.16.17/share-name
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The ubuntu server is also running OpenVPN server. The OpenVPN server uses 10.8.0.0/24 subnet and is assigned 10.8.0.1 ip address. If I connect to the OpenVPN server using the same Windows 10 computer and then access the samba share by typing \\10.8.0.1 in the file explorer, I can see the folder bakro listed.