when DHCP server dynamically distribute IP address, some PC can not get DNS

Publication Date:  2012-10-23 Views:  104 Downloads:  0
Issue Description

Public network---- usg2205BSR - - - - -intranet
1. The user some PC (windows7 and windows XP system), can't normally get DNS distributed by DHCP, but can get IP address.
2. The user cannot obtain the DNS of PC, after repair "local connection", can obtain DNS, or manually designate Internet method of the DNS.
Alarm Information
Handling Process
1. Check the usg2205BSR configuration and there is no problem.
2. Use tracert tracking users PC gateway that do not get the DNS, find that: the IP address PC get is not distributed by usg2205BSR, but distributed by intranet other DHCP server.
3. By the opposite engineer on-site inspection find that: the user intranet has other DHCP server. Close DHCP server and modify intranet segment, and everything is back to normal.
Root Cause
 In the user network have two or multiply DHCP servers, when DHCP server distribute address, IP address is the same, but no DNS.
So the user PC can get IP address, but can't get DNS.
Recommend that users dynamically distribute IP address and DNS for the same network segment in the intranet, only can use a DHCP server.