The check scanner is DHCP server only for its function as check scanner. There is a regular network adapter in the computer, and it has always gotten its IP address from the DHCP server running on the domain controller. It has a DHCP reservation for 192.168.27.113, and that is not the problem. This works perfectly, whether the check scanner's virtual/USB Ethernet connection is enabled or not. This subnet is 192.168.27.0 with gateway 192.168.27.1 that is my router.
When the check scanner's virtual USB/Ethernet connection is enabled, the computer correctly gets a second IP address (currently 192.168.4.123) on the 192.168.4.0 subnet from the DHCP server at 192.168.4.1 on the check scanner, but with no gateway, from the check scanner DHCP server. This is only to communicate between the computer and check scanner across the USB connection. This is also correct and has been working correctly for many months.
Until last week, home folder and network drives would correctly map at logon time per ActiveDirectory home folder definition and login script net use drive mappings. But as of last week, this is not true unless I disable the check scanner's USB/Ethernet network adapter. When it is enabled, I cannot reach any network shares (thus I assume SMB) This is via \MyServerName\Netlogon (or \MyServerName\AnyOtherShareName) or \IPAddressOfServer\ShareName. Since it fails both via DNS name & IP, I have already eliminated DNS as an issue.
At the moment, with the Panini check scanner's USB LAN adapter enabled, here is how it stands:
- Computer's LAN address is 192.168.27.113.
- I can log on locally or remotely via RDP.
- I can ping the domain controller at 192.168.27.3 (or any other computer, internal or exteneral, by IP or name)
- Computer's address on check scanner LAN is 192.168.4.123
- netstat -a shows 139 listening on both LANs:
TCP 192.168.4.123:139 MyComputerName:0 LISTENING [this line does not exist when I disable the Panini adapter
TCP 192.168.27.113:139 MyComputerName:0 LISTENING
TCP [::]:445 MyComputerName:0 LISTENING
When I run netstat -ano, both of the 139 port entries are on PID 4 (System).
When I then disable the Panini check scanner adapter, the scanner no longer has an address on the 192.168.4.0 subnet and therefore no longer listens on that subnet.
Maybe it is not SMB, though. It is whatever port allows me to find & see other computers via UNC paths.
Whether the Panini adapter is connected or not, I can access the shares on this computer from other computers.