samba - Mar 2021 - Windows 10 cannot connect without SMB1

On 02/03/2021 13:55, K.R. Foley via samba wrote:
>
> Initially I started testing with two VMs on the same private network, 
> a Windows client and a Linux VM running Samba 4.11.1. These VMs 
> were/are not physically isolated, but they are on a separate subnet 
> with no routing to/from any other subnet. I have to work in this 
> environment because they are not physical PCs. I got this working, but 
> it is possible that they might have been communicating via SMB1. I 
> then brought up an AWS instance because that is where the initial 
> Samba server will reside (that is why there are different subnets and 
> the VPN). Configured everything, but with 4.11.13. In the meantime the 
> Windows VM has been updated. Now it won't support SMB1 and now my 
> problems start.
>
> Last night, I went back to my initial test VM for the Samba server. 
> The two VMs are on a separate subnet with no routing to/from any other 
> network and the same problem persists. I get the exact same errors. 
> The client still thinks that the server is trying to use SMB1.
>
> Again there is no routing between this subnet and any other subnet. 
> However, the VMs are not physically isolated. This is not really 
> possible in the current environment. There is an older Samba NT4 PDC 
> on the same ESXI with the test VMs, but there is no IP routing and 
> also the domain names are different. Is it possible that this is 
> causing a problem?
>
OK, I have downloaded the latest Win10 ISO, installed it in a VM and it 
joined my Samba 4.13.2 AD domain. I am now of the opinion that it is 
something in your setup that is causing this and I think it may be your 
PDC which relies on two things. SMBv1 and netbios. Netbios does not use 
dns, so this may be replying to the Win10 search for a DC.

Rowland

On 2021-03-02 10:12, Rowland penny via samba wrote:
> On 02/03/2021 13:55, K.R. Foley via samba wrote:
>> 
>> Initially I started testing with two VMs on the same private network, 
>> a Windows client and a Linux VM running Samba 4.11.1. These VMs 
>> were/are not physically isolated, but they are on a separate subnet 
>> with no routing to/from any other subnet. I have to work in this 
>> environment because they are not physical PCs. I got this working, but 
>> it is possible that they might have been communicating via SMB1. I 
>> then brought up an AWS instance because that is where the initial 
>> Samba server will reside (that is why there are different subnets and 
>> the VPN). Configured everything, but with 4.11.13. In the meantime the 
>> Windows VM has been updated. Now it won't support SMB1 and now my 
>> problems start.
>> 
>> Last night, I went back to my initial test VM for the Samba server. 
>> The two VMs are on a separate subnet with no routing to/from any other 
>> network and the same problem persists. I get the exact same errors. 
>> The client still thinks that the server is trying to use SMB1.
>> 
>> Again there is no routing between this subnet and any other subnet. 
>> However, the VMs are not physically isolated. This is not really 
>> possible in the current environment. There is an older Samba NT4 PDC 
>> on the same ESXI with the test VMs, but there is no IP routing and 
>> also the domain names are different. Is it possible that this is 
>> causing a problem?
>> 
> 
> OK, I have downloaded the latest Win10 ISO, installed it in a VM and
> it joined my Samba 4.13.2 AD domain. I am now of the opinion that it
> is something in your setup that is causing this and I think it may be
> your PDC which relies on two things. SMBv1 and netbios. Netbios does
> not use dns, so this may be replying to the Win10 search for a DC.
> 
> Rowland
> 
Thanks. This evening I am going to try isolating the VMs completely. If 
I am unable to isolate them completely, I may just turn off the PDC 
momentarily to test. I will report back with my results.

kr