DNS server priority
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while remotely connected, i can ping the pfsense box (192.168.1.1) but something with DNS isnt working.
C:\Users\admin>ping 192.168.1.1
Pinging 192.168.1.1 with 32 bytes of data:
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64
Reply from 192.168.1.1: bytes=32 time<1ms TTL=64Ping statistics for 192.168.1.1:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 0ms, Maximum = 0ms, Average = 0msC:\Users\admin>ping google.com
Ping request could not find host google.com. Please check the name and try again
.C:\Users\admin>ping 8.8.8.8
Pinging 8.8.8.8 with 32 bytes of data:
Reply from 8.8.8.8: bytes=32 time=22ms TTL=52
Reply from 8.8.8.8: bytes=32 time=22ms TTL=52
Reply from 8.8.8.8: bytes=32 time=23ms TTL=52
Reply from 8.8.8.8: bytes=32 time=24ms TTL=52Ping statistics for 8.8.8.8:
Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
Minimum = 22ms, Maximum = 24ms, Average = 22mshmmmmmmm. i cant web into 192.168.1.1
is it possible to reboot pfsense via command line from a network PC?
EDIT- i just tried IE and i can login to pfsense using IE. should i reboot the box or is there something else i should try before i attempt to reboot it?
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is it possible to reboot pfsense via command line from a network PC?
yes it's in menu option.
interesting. ever since i disabled that DNS forwarder option, i cant get anything to work.
you need firewall rules to allow access to dns service on lan.
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is it possible to reboot pfsense via command line from a network PC?
yes it's in menu option.
interesting. ever since i disabled that DNS forwarder option, i cant get anything to work.
you need firewall rules to allow access to dns service on lan.
it is in the menu option from a remote PC on the network? i dont follow.
also, if i needed rules to allow DNS server on the LAN, it would have been nice to know that prior to unchecking that box. ;D
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ok, i just enabled DNS forwarder to make sure sites can resolve. this is probably something that i should work on while i am on site.
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@tomdlgns:
for my LAN devices, i want to make sure that they point to pfsense (192.168.1.1) for DNS, which is what is currently in place now.
So why would tomdlgns want to disable the DNS forwarder as suggested:
@marcelloc:If you want to remove 127.0.0.1 from list, disable dns forwarder in services menu.
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If you want to remove 127.0.0.1 from list, disable dns forwarder in services menu.
Don't do this unless you really know what you're doing, it'll break DNS on all LAN clients in the default out of the box setup.
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So why would tomdlgns want to disable the DNS forwarder as suggested:
@marcelloc:If you want to remove 127.0.0.1 from list, disable dns forwarder in services menu.
he wants to use only opendns servers:
i want to use the openDNS servers (208.67.222.222, 208.67.220.220).
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he wants to use only opendns servers:
i want to use the openDNS servers (208.67.222.222, 208.67.220.220).
Right, but his LAN clients are configured to use pfSense as their name server:
@tomdlgns:for my LAN devices, i want to make sure that they point to pfsense (192.168.1.1) for DNS, which is what is currently in place now.
If pfSense doesn't have DNS forwarder (or equivalent) enabled how will his LAN clients get name service from pfSense?
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tomdlgns did not specified a complete scenario, he just asked how to use his opendns servers.
The way he asked, creating lan rules to allow dns queries to 208.67.222.222 and 208.67.220.220 will work.
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tomdlgns did not specified a complete scenario, he just asked how to use his opendns servers.
The way he asked, creating lan rules to allow dns queries to 208.67.222.222 and 208.67.220.220 will work.
How do I do this?
That was the next part of my question, but I didn't want to tackle it until I got home.
My goal is to have network computers point to 192.168.1.1 for DNA, the pfSense box, and I want to use opendns servers.
I am using opendns servers now, but if a network user inputs 8.8.8.8 or other third party servers in their nic settings, they will bypass the opendns servers.
Basically, I want to intercept all DNA lookps just before they leave the network. I was able to do this with dd wrt firmware on a Lindsay's router before I switched to pfSense.
Thanks
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This way you need to block dns queries on lan rules and enable dns forwarder.
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This way you need to block dns queries on lan rules and enable dns forwarder.
sure, but is there a guide to do this? if i knew how to do it, i wouldnt have posted in here.
:)
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Do you need help creating rules or changing dns servers?
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Do you need help creating rules or changing dns servers?
under the general tab, right now, i have the openDNS servers and the local host address
127.0.0.1
208.67.222.222
208.67.220.220with the help from you guys in this thread, i have been able to eliminate the ISP DNS Servers from that list.
it appears that is working w/o any issues.
the next step is to create rules, i suppose that is next, that will allow me to intercept DNS lookups. that might not be the right word/phrase.
but what i would like to accomplish is to force a certain set of DNS servers to be used regardless of what the user has used on their device.
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You could add the following firewall rule (On Firewall -> Rules, click on the LAN tab, click on the lowermost "+": Action=Block, Disabled='not ticked', Interface=LAN, Protocol=TCP/UDP, Source=any, Destination=( not='ticked', Type=LAN address,) Destination port range=DNS, Log='ticked')
This will block any attempt by a system connected to the LAN interface to access (by TCP or UDP) a DNS Server (port 53) on any IP address other than the pfSense LAN IP address and will log in the system log any such attempt.
If you have other firewall rules on the LAN interface you need to check that a rule higher up the list doesn't allow this rule to be bypassed. (Rules are processed from the top down, processing stops on the first match.)
The logging gives some information to help track down offenders.
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thanks, i will try this.
if i do this, can i disable the DNS forwarder option?
my LAN PCs are using 192.168.1.1 for the DNS server, which is what i want, but i didnt set that under the DHCP settings for the LAN interface.
is it pulling that by default?
also, i dont mind leaving the DNS forwarder option as is, i dont want to break anything, but i also dont see the need to have 127.0.0.1 as a DNS server.
thank you for your help.
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@tomdlgns:
if i do this, can i disable the DNS forwarder option?
No because @tomdlgns:
my LAN PCs are using 192.168.1.1 for the DNS server, which is what i want,
@tomdlgns:
but i didnt set that under the DHCP settings for the LAN interface.
DNS entries on DHCP page will override default of pfSense xxx interface.
@tomdlgns:
i also dont see the need to have 127.0.0.1 as a DNS server.
Is there a problem with pfSense using DNS forwarder for name resolution?
Suppose you didn't have 127.0.0.1 on pfSense DNS list. This would mean all DNS requests from pfSense would go to OpenDNS. OpenDNS does not know how to resolve names of systems on your local network. Do you want pfSense applications to not have access to name resolutions of "local" systems.
How would pfSense
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@tomdlgns:
if i do this, can i disable the DNS forwarder option?
No because @tomdlgns:
my LAN PCs are using 192.168.1.1 for the DNS server, which is what i want,
@tomdlgns:
but i didnt set that under the DHCP settings for the LAN interface.
DNS entries on DHCP page will override default of pfSense xxx interface.
@tomdlgns:
i also dont see the need to have 127.0.0.1 as a DNS server.
Is there a problem with pfSense using DNS forwarder for name resolution?
Suppose you didn't have 127.0.0.1 on pfSense DNS list. This would mean all DNS requests from pfSense would go to OpenDNS. OpenDNS does not know how to resolve names of systems on your local network. Do you want pfSense applications to not have access to name resolutions of "local" systems.
How would pfSense
no, there is no problem with pfsense using 127.0.0.1 to lookup local name resolution. if that is what it is doing, then i will leave it alone.
thank you.
i wasnt sure exactly what it did, which is why i asked.
if i create the rules posted above, pfsense will force openDNS servers regardless of what the user has set on their device, correct?
that is mainly what i am looking to do.
thanks.
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@tomdlgns:
if i create the rules posted above, pfsense will force openDNS servers regardless of what the user has set on their device, correct?
It was a single rule and it needs to be correctly positioned with respect to other rules you might have.
Here's how the overall thing works: pfSense uses only OpenDNS and the pfSense DNS forwarder for name resolution. The firewall blocks any attempt by a system connected to the LAN interface to use a DNS server other than pfSense. Note the firewall doesn't "automatically" change an attempt by a LAN system to use (say) Google name server into an attempt to use OpenDNS. An attempt by a LAN client to use anything other than the pfSense box as their name server will be blocked generally resulting in some sort of error report which will probably send the user to tech support (you?) who will investigate and find they are attempting to break the usage rules and appropriate discipline can follow.
It might be possible to have a NAT type firewall rule (or rules) to automatically change a "violating" DNS access into a conforming DNS access.
This configuration doesn't do anything to block access to name servers providing service on non-standard ports. If you find such name servers then you could add appropriate firewall rules.
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@tomdlgns:
if i create the rules posted above, pfsense will force openDNS servers regardless of what the user has set on their device, correct?
It was a single rule and it needs to be correctly positioned with respect to other rules you might have.
Here's how the overall thing works: pfSense uses only OpenDNS and the pfSense DNS forwarder for name resolution. The firewall blocks any attempt by a system connected to the LAN interface to use a DNS server other than pfSense. Note the firewall doesn't "automatically" change an attempt by a LAN system to use (say) Google name server into an attempt to use OpenDNS. An attempt by a LAN client to use anything other than the pfSense box as their name server will be blocked generally resulting in some sort of error report which will probably send the user to tech support (you?) who will investigate and find they are attempting to break the usage rules and appropriate discipline can follow.
It might be possible to have a NAT type firewall rule (or rules) to automatically change a "violating" DNS access into a conforming DNS access.
This configuration doesn't do anything to block access to name servers providing service on non-standard ports. If you find such name servers then you could add appropriate firewall rules.
i am not sure how do it in pfsense, i was able to do it with my linksys router that had DD-WRT flashed on it.
basically, i could set anything i wanted on a network computer for the DNS servers…
i did several tests. i used bogus IP addresses on the client PC and i was still able to browse the internet.
if i went to welcome.opendns.com i saw the message that confirmed i was using their servers.
the network i was running at the time was 192.168.1.0 /24 and this was the DNS i was using on the client PC: 192.168.250.3 (just something random to make sure the firewall was ignoring the DNS server i had in my network settings) and DNS still worked because it forced openDNS servers to be used.
i used this command in the dd-wrt router to intercept DNS that client machines were trying to use.
"Configure DNSMasq for OpenDNS DNS forwarding
Go to Services tab » Services sub tab » Services Management section » DNSMasq sub section
Enable both DNSMasq and Local DNS options
In the Additional DNSMasq Options text box, enter:
no-resolv
strict-order
server=208.67.222.222
server=208.67.222.220
Click Apply Settingsand
You can prevent users from using their own DNS servers (and hence get around content filtering) by intercepting DNS queries and forcing them to use the DNS servers you specify.
Go to Administration tab » Commands sub tab
In the Commands text box, enter:
iptables -t nat -A PREROUTING -i br0 -p udp –dport 53 -j DNAT --to $(nvram get lan_ipaddr)
iptables -t nat -A PREROUTING -i br0 -p tcp --dport 53 -j DNAT --to $(nvram get lan_ipaddr)
Click Save Firewall (note: your WAN interface will be restarted)"just in case someone reads this later, these are NOT directions for the pfsense firewall. i just wanted to point out how i was intercepting DNS lookups with dd-wrt.
the rule that was posted above might work, but i'd like to confirm that i am on the same page before i create rules in pfsense.
