This article discusses how to resolve an issue where backups are failing and a reboot of the server seems to clear up the issue for a while but then then issue reoccurs.
Backups are failing with message cannot connect to client.
Windows Server 2003
Windows Server 2008
Symptoms / Description
Backups are failing but a reboot of the server seems to clear up the issue for a while but then then issue reoccurs.
Our agent uses 2 ports for communication with the DPU appliance. Port 1743 is known as our command port and port 1745 is used for data transfer. It is possible for some other process to use 1745 and cause our backup to fail. One way to determine whether another process is using port 1745 is to run some simple network commands.
netstat –ano > C:\ports.txt
You can then use notepad or your favorite text editor to check the file for what processes are using what ports. The ‘-o’ flag shows what PID has the port open. Search for port 1745 and see if it is in use.
Resolution / Workaround / Execution Process
You can edit the master.ini which is installed by default to C:\PCBP\master.ini. Search the file for data=1745. You can change this to data=1744. This change stops using the single port 1745 for data transfer and looks for any random open port for the data transfer.