Authentication Failed Because the SVN3000 Time Zone and Time Are Incorrectly Set

Publication Date:  2012-07-20 Views:  121 Downloads:  0
Issue Description
The SVN3000 and AD server were configured for joint authentication. After the user set the AD server parameters on the SVN3000 and searched the account of the AD server, the user attempted to authenticate the account. However, the authentication failed. A message was displayed stating "Incorrect user name or password."
Alarm Information
Handling Process
Enable debug ad and debug ldap on the SVN3000. Authenticate the client to obtain the debugging data. The debugging data is as follows:

debugging ad packet
debugging ldap packet
terminal debug

0.446918679 SVN3000 %%01AD/8/debug(d):

[AD(pkt):] Make kerbores AS Request packet successfully,username: test111

0.446918819 SVN3000 %%01AD/8/debug(d):
[AD(Pkt):] Send packet to AD-server(ServerIP:,Port:88)

0.446918949 SVN3000 %%01AD/8/debug(d):
[AD(Pkt):] Send kerbores AS request packet successfully.

0.446919069 SVN3000 %%01AD/8/debug(d):
[AD(Pkt):] Recevied kerbores packet successfully, username: test111.

0.446919209 SVN3000 %%01AD/8/debug(d):
[AD(Pkt):] Kerberos server's response is bad, ErrorCode: 37.

0.446919339 SVN3000 %%01AD/8/debug(d):
[AD(Pkt):] Clock skew too great.

0.446919429 SVN3000 %%01USER/8/debug(d):
Virtual Gateway Client: Login failed. User information error.
The debugging message [AD(Pkt):] Clock skew too great." indicates that the time is greatly different on the client and the server. The AD authentication requires that the time error be shorter than five minutes between the client and server. Otherwise, the authentication fails. The SVN client is authenticated on the AD server through the SVN3000 proxy, the debugging message indicates that the time is greatly different on the SVN3000 and the AD server.
After the time of the SVN3000 is aligned with that of the AD server, the authentication still fails. Check the debugging data. The message of "Clock skew too great" persists. It was found that the time zone were not set on the SVN3000. After the time zone was set to (GMT 08:00) Beijing, Chongqing, Hong Kong, Urumqi, the authentication succeeds
Root Cause
The account of the AD server can be searched on the SVN3000, indicating that the AD server is successfully connected to the SVN3000. The possible causes are as follows:
1.      The AD server is faulty.
2.   The SVN3000 is not correctly configured.  
To configure joint authentication between the SVN3000 and AD or LDAP server, ensure that the time zone and time are correctly set. The time error between the SVN3000 and the server must be within five minutes. Otherwise, the authentication fails.