We have a corporate Canon IR copier with scan over network feature enabled. But we cannot scan to the shared folder at the smb server.
So, lets find why.
At the beginning I suspected a permission issue on the share, so I checked the permissions that seems correct, everyone is given read and write acces to the share.
Second, I started process monitor on the computer who hosts the share, but it did not give me any clue. So I deduced that the issue is related to the network and I have to do a captue the packets on the Canon’s Ethernet interface.
To do so, I set up the SPAN (Switch Port Analyzer) feature on the Cisco Catalyst Switch to copy all the network trafic from the Canon’s interface to another interface on which I plugged a PC with Wireshark installed on it.
Here is the wireshark’s capture result:
We can see the canon copier sending Netbios broadcasts asking for the IP address of the host named AL1XXXX7P (The smb server). As it didn’t receive any response he sends a dns query to the DNS Server asking for the IP of the AL1XXXX7P.DOMAIN.LOCAL host, and the DNS server replies with the IP 10.x.x.13.
Next the copier sends a Netbios query to the 10.x.x.13 host trying to initiate a communication on UDP port 137. the smb server replies that he can’t communicate on port 137.
Ok, now we know why the scanned documents are not sent to the the smb share. So Why the SMB server cannot use his UDP 137 port?
The reason is that, a few days ago, I’ve enabled the “Disable Netbios over TCP/IP” option of the network interface. By enabling Netbios over TCP/IP again I was able to send scans again from the Canon copier to the SMB Server.
In the following screenshot the Wireshark trace when the the Netbios communication betwen the two devices succeed: