No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>

Reminder

To have a better experience, please upgrade your IE browser.

upgrade

User’s DNS configuration error causes can’t access to the Internet

Publication Date:  2012-11-22 Views:  46 Downloads:  0
Issue Description
Networking: pc----USG2110----internet. Users can ping public network gateway and local DNS, but cannot open the web page.
Alarm Information
None.
Handling Process
1. Guide the user to change the DNS address for the correct address, the problem is solved. 
Root Cause
1. Landing equipment inspects packet filtering rules and NAT configuration, they are correct. Eliminate configuration problem.
2. From the equipment can ping DNS public network gateway, eliminate network reason.
3. Because users PC cannot ping and remote login, doubt it is caused by mtu, try to change the mtu value of the internal network interface, has no effect.
4. Check session table, check the NAT translation, found the problem. User NAT translation is no problem, but found a large number of DNS requests, but target address is the private network address.
[jiangujiang]dis firewall session table
DNS:192.168.0.3:50389[115.148.46.74:30192]-->10.33.80.18:53
DNS:192.168.0.3:49786[115.148.46.74:30199]-->10.33.80.18:53
DNS:192.168.0.3:63430[115.148.46.74:30196]-->10.33.80.18:53
Suggestions
1. When meeting the situation that users can’t access to the Internet, can check session table, check whether the NAT translation has problem and the user DNS requesting address is correct.

END