DMZ - 1:1 NAT , and also "Hybrid"
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I'm doing my first 1:1 Nat in hybrid mode.
I have a DMZ , that is "auto natting due to Hybrid mode".
I have now made a 1:1 nat to a VIP on the outside , and the1:1 NAT seems to have precedence.Meaning the 1:1 Nat is the ip that is listed if i go to "myip.com" from the server.
Is that a "Best practice 'ok' " - Meaning - That i don't have to "disable" the "Auto nat on the /24 DMZ" made by hybrid mode ??
Else i have to go to Manual nat (Not preferred by me) , and disable the "Auto Nat"
This is my first 1:1 Nat .... "Be kind" ...
/Bingo
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@bingo600
In hybrid mode, manually added NAT rules ever have precedence over automatically added ones.Is that a "Best practice 'ok' " - Meaning - That i don't have to "disable" the "Auto nat on the /24 DMZ" made by hybrid mode ??
Since you have added an 1:1 NAT rule for the DMZ, I think you have achieved what you was intending. So it's fine.
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Still figthing this 1:1 NAT (My first).
I have a web server that i want to 1:1 nat to my outside (/27)
Does a 1:1 NAT require a VIP defined on the WAN for the public nat ip ??I tried to do that , but it semed like i got pfSense GUI when trying to https to the "Outside NAT (WAN)" , not the web server.
I deleted the WAN Alias IP , and just left the 1:1 NAT definition ....
That might be my mistake ....Things worked yesterday , but not this morning.
Now i see ARP resolve errors for my 1:1 NAT WAN ip's
I suppose the ARP that made it work yesterday is "aged out" or ??I'm in doubt if i need a VIP Alias for the "outside" , and then a 1:1 NAT to map it to the inside ?
I was just "panicing" a bit when i'm 99% sure i could reach the pfS GUI when doing the VIP Alias... But i might not have had NAT in place.
The VIP + 1:1 NAT was my first intuition , and then i deleted the VIP ...
As i thought the system might be smart enough to figure out that a 1:1 nat to the outside , would require the pfS to respond with the wan if mac.I'm doing this from "remote" on a production system.
So just "trying" .... Well i "chickened out" ...Does a 1:1 NAT require a VIP defined on the WAN for the public nat ip ??
And when i do the 1:1 NAT to the VIP, then it will override the pfS wan IF address ?.
So i'll see the "Inside natted webserver" not the pfS GUI ?/Bingo
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Well i redid the VIP Aliases for my 3 x 1:1 NAT , and things started to work.
Now my 3 x Outside ip's have a static/permanent arp entry , due to the VIP Aliases.So it seems like you'd need the VIP 's if you want to 1:1 NAT a server to the "Outside"
That is the L2 part of the WAN "trickery".
Just remember to do the 1:1 NAT right after , else the VIP will respond as an "Alias IP" of the Fwall Wan ip address./Bingo
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Also it seems like a VIP Alias belongs to TFW (kind of makes sense)
But i did not expect it to when I make a 1:1 NATSo my (UP high rule) of deny any to TFW , blocks comms (STUN) from "Server 1" to "Server 2".
Server 1 & 2 are in a DMZ , and both are 1:1 natted to the FW outside.
I see block by (deny any TFW) rule .
Server1 - DMZ Inside ip UDP 3478 , to Server2 (Public outside). -
@bingo600 said in DMZ - 1:1 NAT , and also "Hybrid":
I have now made a 1:1 nat to a VIP on the outside , and the1:1 NAT seems to have precedence.
It has. BiNat is always on top of outbound nat rules in the resulting pf.rules file so they take precedence. Also Port Forwardings (or better "redirects") are on top of them, so first matched are PFW/redirects, then 1:1 NAT (binat) and last ones are outbound NAT rules. After that the firewall rules start.
Is that a "Best practice 'ok' " - Meaning - That i don't have to "disable" the "Auto nat on the /24 DMZ" made by hybrid mode ??
You don't have to, but I'm always recommending disabling auto/hybrid NAT and go with manual rules as they allow much more finetuning and you can delete unnecessary outbound NATtings and therefore disable potential security risks. Example: if you've created an OpenVPN remote access server, the tunnel network gets auto-added to auto outbound NAT rules. If you only want to serve your VPN users a split tunnel and never want them to access the internet via the VPN connection (and e.g. suck away bandwith from other services) then you won't have need for that and by removing it, you can't accidentally run into the situation.
But otherwise it's fine.
Does a 1:1 NAT require a VIP defined on the WAN for the public nat ip ??
That depends if that IP is either routed to you WAN IP or if it's another IP in the same subnet where your WAN IP is and otherwise wouldn't "arrive" on your WAN interface:
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same subnet: you have 192.0.2.194 on your WAN, 192.0.2.193 is your ISPs upstream router. You have the rest of the subnet 192.0.2.192/29 for your own use (.194-.198, you already used 194 for pfSense). If you want to 1:1 NAT e.g. 192.0.2.195 then YES, you have to create an VIP on pfSense so it acutally reacts to packets for .195, otherwise it would not see it at all.
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routed subnet: as above you have configured 192.0.2.194/29 as your WAN and .193 as upstream router. But your ISP was friendly and added another /29 subnet to you and routed it to your IP .194. So now you have an additional subnet, let's call it 192.0.2.248/29. The IPs of that additional subnet already arrive on your WAN interface due to being routed by your upstream provider, so you can do with them as you like. You don't have to create an alias VIP here, as the IPs already arrive on your interface and as you are NOT using them on pfSense itself(!) you can just 1:1NAT them to another system and be done with it. Be aware that only works if
a) the additional IPs are routed to you like above and
b) you are NOT using the IPs on an actual service on pfSense itself (e.g. haproxy, VPN service etc.) that would need to bind to that IP.
Depending on which is your case, the proceedings are slighty different.
Does a 1:1 NAT require a VIP defined on the WAN for the public nat ip ??
Depends on the above
And when i do the 1:1 NAT to the VIP, then it will override the pfS wan IF address ?.
Not sure what you mean by that, but no, it doesn't override anything but you have to check what your outbound NAT rules use as NAT address. But the 1:1 NAT is separate from that. You just have to double check your ruleset, as you have to add a rule for the BiNAT entry that has the internal IP as destination, NOT the external/public IP you used for the NAT. If you allow e.g. from any to 10.20.30.123 port 443 then you only open up HTTPS on that internal system after it being NATted correctly. If you create an IP Alias on pfSense, the WebUI is automatically bound to every IP (0.0.0.0) and therefore if your NAT rule is disabled/doesn't work correct you would expose pfSense WebUI to the internet.
That's why we recommend to move the WebUI port to another port (e.g. 10443, 1443, 4443) so you don't accidentally open up the WebUI to the internet. You'd also have to disable the automatic WebUI redirection (so ports 80 and 443 won't get redirected to your new port) then the WebUI should be safe and you don't expose yourself by accident.
Also it seems like a VIP Alias belongs to TFW (kind of makes sense)
TFW?
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TFW = This Firewall (The built in "alias")
I have a public /27 as a flat (L2 ISP provided Vlan) subnet , so i have to do the VIP (thanx)
I tried wo the VIP , and could see the unresolvable arps for the outside ip in PFs arp table.The VIP Alias solved it , but it behaved a bit strange ... I thought to begin with.
It seems like the VIP's are included in the "This Firewall Alias (TFW) / An ip where pfSense services ansvers." , so i when i did a HTTPS to the VIP i got the pfSense GUI -- "And panicked"Now that i have thought about it , it kind of "makes sense" as the alias is a pfsense ip.
I had just expected that when i did a 1:1 nat using that ip , that it would not belong to TFW anymore.Well ...
I seems like i have not done anything "bad" , when having to do a VIP Alias , before pfSense vould respond to an arp request.
Thank you guyzz.
I was brought up with PIX/ASA
/Bingo
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@bingo600 said in DMZ - 1:1 NAT , and also "Hybrid":
It seems like the VIP's are included in the "This Firewall Alias (TFW) / An ip where pfSense services ansvers."
of course, that is working as intended and documented. TFW always includes EVERY IP the firewall itself is configured on. That includes e.g. LAN, VPN transfer networks etc. that's why you should be careful using that keyword.
So if you have WAN rules, double check them and remove "this firewall" with e.g. "wan address" or the appropriate alias IP or create custom aliases for your use :)
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I had not hoped it behave that way ...
Aliases/VIP*s should not be in TFW IMHO.Now i know
Thanx Jens
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I thought that Deny any 443 TFW would protect my firewall IF 's only ... (It does + Aliases).
I did not expect that ...
Well i'm learning every day due to ppl . like you - and "The hard way"
In fact an Alias belongs to TFW ... I had just hoped with an 1:1 Nat on it it would not ...
Well im smarter today then yesterday , and TFW might seem nice in a simple config , but ... WATCH out ...
/Bingo
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@bingo600 said in DMZ - 1:1 NAT , and also "Hybrid":
Aliases/VIP*s should not be in TFW IMHO.
They aren't. Not Aliases. But VIPs are ON THIS firewall, so it fits the description and the docs to the letter. All IPs that are on interfaces on that firewall. So that matches.
In fact an Alias belongs to TFW ... I had just hoped with an 1:1 Nat on it it would not ...
It still does but if you have defined a BiNAT entry, then the IP gets rewritten FIRST and thus no longer matches "this firewall" as the packet now is destined for the internal IP and has to match it. But it's way too easy to make errors that way so just define the IP you want to match (either by WAN address or by selecting the VIP you want) and use that in NAT/Rules so you're safer that way :)
Also move the WebUI port away from 443 and disable the auto redirect for it, that safes many headaches! We recommend using 4443 and explicitly blocking that on WAN-style interfaces can help avoid the "oopsie" of presenting your webUI to the world :) The rule is just a bonus though as you don't commonly have 4443/tcp allowed inbound anyways.