(Original) access conditions for UNC paths

I have summarized some experience in UNC path access, which can be divided into intra-domain and non-domain situations.

1. If a machine in the domain (including machines in the two regions with mutual trust) can directly access the shared file through a UNC path.

2. Two machines (a and B) have been added to the domain (or belong to a domain with mutual trust). If a is logged on with a domain user account, if machine B is logged on locally, the shared folder of machine B can be accessed from the UNC path on machine A, but machine B cannot access the shared folder of machine A through the UNC path. This is because, machine A is logged on to the domain user. He can obtain the address and service bill of machine B from the DC (DAI Youwei's ad Configuration Guide p195 ). But machine B is not in the domain, so you cannot find the address of machine A on the DC and get the service bill. Therefore, machine B cannot access machine A through the UNC path.

 
3. If the IP segments of machines A and B are the same, they are not added to the domain. no matter whether they are in the working group status or they are domain members, they use a local account to log on. The two machines do not have the same account and password (for example, both have a hyj account and the password is 111), so they cannot access the shared folder through UNC.

4. We can see from the general description that there are two ways to access server B through the UNC path of server:

One is how a sends a query address and request a service bill to DC (A and B are added to the domain, and at least a must be logged on to the domain account), so that DC can be introduced in the middle.

The other is that both machines must have the same local user account and password. In this way, a can find the matching machine by sending packets to the specified host name (the UNC path contains the machine name, for example, // server1/Director) in the LAN, then get the permission for this machine.

Therefore, as long as the above two conditions are met, you can use the UNC path for access.

In Case 2, if a cannot find B through DC, then if AB has the same local user account and password, they can also access B through the UNC path.

All the above conclusions have been proven.