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OpenDNS Access-list
I have the following access-list on a Layer 3 switch to allow access to OpenDNS for a specific group of PCs.
When I test by doing a DNS lookup, it fails. I can see the number of hits going out increasing but the replies do not get any hits.
I did a Wireshark capture from our Firewall to make sure it was not the cause of the problem by denying the reply traffic back in but it does allow it and then gets dropped by the switch (I am guessing) which sends an ICMP unreachable back to OpenDNS. Do I can see the DNS query to OpenDNS, the reply from open DNS and then the ICMP unreachable from the switch which makes me think the switch is the one dropping the returned traffic.
Can anyone see anything wrong with the following access-list that might be causing the traffic to be blocked?
Extended IP access list PCL_Access_In
20 permit udp 192.168.95.0 0.0.0.255 host 208.67.220.220 eq domain log (473 matches)
30 permit udp 192.168.95.0 0.0.0.255 host 208.67.222.222 eq domain log (648 matches)
Extended IP access list PCL_Access_Out
20 permit udp host 208.67.220.220 192.168.95.0 0.0.0.255 eq domain log
30 permit udp host 208.67.222.222 192.168.95.0 0.0.0.255 eq domain log
interface Vlan10
description PCL_Machines
ip address 192.168.95.1 255.255.255.0
ip access-group PCL_Access_In in
ip access-group PCL_Access_Out out
Thanks in advance
When I test by doing a DNS lookup, it fails. I can see the number of hits going out increasing but the replies do not get any hits.
I did a Wireshark capture from our Firewall to make sure it was not the cause of the problem by denying the reply traffic back in but it does allow it and then gets dropped by the switch (I am guessing) which sends an ICMP unreachable back to OpenDNS. Do I can see the DNS query to OpenDNS, the reply from open DNS and then the ICMP unreachable from the switch which makes me think the switch is the one dropping the returned traffic.
Can anyone see anything wrong with the following access-list that might be causing the traffic to be blocked?
Extended IP access list PCL_Access_In
20 permit udp 192.168.95.0 0.0.0.255 host 208.67.220.220 eq domain log (473 matches)
30 permit udp 192.168.95.0 0.0.0.255 host 208.67.222.222 eq domain log (648 matches)
Extended IP access list PCL_Access_Out
20 permit udp host 208.67.220.220 192.168.95.0 0.0.0.255 eq domain log
30 permit udp host 208.67.222.222 192.168.95.0 0.0.0.255 eq domain log
interface Vlan10
description PCL_Machines
ip address 192.168.95.1 255.255.255.0
ip access-group PCL_Access_In in
ip access-group PCL_Access_Out out
Thanks in advance
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Thanks CraigBeck, removing the access-list from the Out direction fixed the issue.
Can you have a look at the Cabling on Swtich end connecting to Specific Hosts .I hope there is Cross Cabling done in between Switch and Hosts that is the reason you are getting Destination Host Unreachable at Firewall end.Or you can just change the switch and look for the Ping Status .