I just read some articles to mention that why the Windows 7 slow logon to Windows 2K8 DC, some articles said that if the DC is a multi-home server, it will cause this problem.
I am not sure if it is 100% apply to my case but my DC is a multi-home server because it is running as a file server too and this server has 3 network interfaces, one for LAN and 2 for iSCSI SAN. The ip address for iSCSI SAN is different from LAN.
This server is the first DC in my domain and I have another 2 DCs in LAN as backup. My current DNS is pointing to there
IP address : 192.168.1.55
Subnet mask : 255.255.255.0
Gateway : 192.168.1.254
DNS Server: 192.168.1.3, 192.168.2.1, 192.168.1.2
The ip 192.168.1.2 is my first DC.
Based on this information, how can I improve the user's logon speed?