I have configure Cisco ACS v4.1 to control network accessing. When a domain user logon, it takes a few seconds to logon using credentials. However, it takes around 1 minute to get the authentication successfully. The problem is the computer can't talk to the DHCP and DC. The network status shows Limits or not connectivity. The ipconfig shows it uses auto ip address 169.254.x.x. To obtain an IP or talk to the DC, the user needs to enter ipconfig /renew or re-logon. How do you troubleshoot it?
No, it is not VPN user. Just LAN users. If we don't configure port to use dot1x, it works and it has been working fo rmany years. The normal logon takes just seconds without ACS. I also find the computer will receive an IP address from DHCP after logon 5 minutes. The problem is that authentication takes too longer to get pass, the computer uses windows credentials to logon. The port led take over one minutes to become green from orange.
What I did is running wireshark after logon without network and plug the cable. Based on the sniffing, The computer try to talk to the DHCP and can't get an Ip until 25 seconds.
Normally, it takes the XP logon and maps the network drives in 5 seconds if it doesn't connect to authentication port.
