don't understand some firewall log activities

Posted on 2001-06-04
Last Modified: 2013-11-16
this is the screen capture from the checkpoint firewall log viewer. Please take a look first

I always find that these two hosts connect my firewall thru service is domain-udp.
Actually these two hosts is from our ISP

What are they doing ?
Question by:adrianmak
  • 2
LVL 12

Expert Comment

ID: 6154773
-Looks to me to be simple DNS traffic. port 53 UDP protocol 7. You cannot resolve sites from the lan with regular DNS queries..
LVL 12

Expert Comment

ID: 6154774
-Looks to me to be simple DNS traffic. port 53 UDP protocol 7. You cannot resolve sites from the lan with regular DNS queries..

Accepted Solution

Haho earned 5 total points
ID: 6159094
yes it does seem like DNS query packets..
DNS query uses UDP but DNS zone transfer uses TCP.
Is your servers a DNS server.. that would explain your ISP querying your server for because your server is the authorative DNS server for


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