Network vs. interactive logon
Windows recognizes different types of logon with subtly different security implications. Bitvise SSH Server can be configured, on a per-account or per-group basis, to use either of the following two logon types:
Network logon. By default, this logon type is configured in SSH Server Advanced settings for both Windows and virtual group settings entries. This logon type is therefore used, by default, for all accounts.
Use of the "network" logon type allows the user to log in via SSH even if the underlying Windows account is not granted the Windows security privilege Log on locally. However, on Windows Server 2003, the default filesystem permissions normally block access to cmd.exe and other command line tools when a logon session does not have the "interactive" logon type.
Interactive logon. Use of the "interactive" logon type requires a Windows account to be granted the Windows security privilege to Log on locally. By default, this logon type is not used by the SSH Server because a significant number of Windows servers are configured in such a way that this privilege is not granted for non-Administrator accounts.
For some purposes, the "interactive" logon type is required. For example, it is not possible to access server-side printers in an SSH terminal session unless the SSH user is either an administrator, or has the "interactive" logon type. The "interactive" logon type is also required on Windows Server 2003 for terminal shell access.
Selecting the right logon type
We recommend that users who require terminal shell access use the "interactive" logon type. It will usually also make sense for them to log in via SSH as Windows users, not as virtual accounts.
On the other hand, we recommend that users who will use only file transfer and/or tunneling use the "network" logon type. If this use is outside of a domain environment, it may also make sense (less overhead) to create for these users virtual accounts, which are internal to Bitvise SSH Server, instead of creating a separate account in Windows for each user.