OPNsense Forum

Archive => 18.1 Legacy Series => Topic started by: opnsense@f2f10.com on March 13, 2018, 11:00:09 am

Title: Automatic NAT Rules Generation
Post by: opnsense@f2f10.com on March 13, 2018, 11:00:09 am
HI all,

Just deployed pfSense and opnSense together and noticed a small difference.
https://doc.pfsense.org/index.php/Automatic_NAT_Rules_Generation

pfsense says this above and does it. In my case, I have a static routes to all my internal network (10.16.0.0/16). Indeed, I see this on NAT. This is good as I'd like to have my other internal networks transverse this firewall out, but I don't want my firewall has interface to those remote networks.

On opnSense, this seems not the case; after a fairly troubleshooting with tcpdump, I realized that this has to be manually added in NAT rule to get it work.

My question is, is this a "intentionally" done difference, or , is it a "bug".  I am ok with either method of getting it to work, just want to clarify.

Thanks
peng

Title: Re: Automatic NAT Rules Generation
Post by: dcol on March 13, 2018, 04:28:58 pm
OPNsense does have auto rules generation which is set in the 'Filter rule association' when using 'Pass'.
I am unsure why it also has all the other NAT created rules in the drop down. Maybe to properly associate the FW rule to the NAT rule.
One thing I have noticed though is you should delete the NAT rule and recreate it if you make a change to the rule or it may not generate the Firewall rule correctly. OPNsense doesn't seem to like to make changes to a firewall rule from an existing NAT PF rule. NAT rules seem to always generate a proper firewall rule on its creation.
Title: Re: Automatic NAT Rules Generation
Post by: franco on March 14, 2018, 06:24:50 pm
That's a fairly interesting setup with overlapping 10.16.x.y address spaces. Would you mind giving a full IP setup of your WAN and LANs... I don't understand it very well.


Thank you,
Franco