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LA_Medina_32319's avatar
LA_Medina_32319
Icon for Nimbostratus rankNimbostratus
Jan 09, 2018

DNS not reachable via UDP/Port 53

We have recently added an external DNS lookup server address in our Link controller under the System --> configuration --> device --> dns --> DNS Lookup Server List However, when we do a normal nsl...
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youssef1's avatar
youssef1
Icon for Cumulonimbus rankCumulonimbus
Jan 09, 2018

Hello,

 

Regarding your last comment "Port 53 seems to be open as well". It's normal because telnet use TCP only.

 

Can you tell me if you have a Fw between your LC and your ISP. Because as you explain you can reach the google dns trough TCP but not UDP so I suppose that rooting is working fine and this problem can come maybe from perimeter security...

 

Regards,