I’ve got a question to setup a rule to reach a Wifi Printer which is installed on Blue.
At the moment I did something like this:
Source = StandardNetwork = Green
No Nat
Target = IP from the Printer on Blue
Protocol = ALL
Accept
Now I can Ping the Printer, but unfortunately nothing more. OperatingSystem couldn’t connect the printer.
Has anyone an idea how to set this up correctly?
You don’t need a firewall rule to access things on Blue from Green. Green is open to accessing machines on Blue as standard. Machines on Blue can not access anything on Green.
How were you trying to connect to the printer with your operating system, with CUPS?
Often OS’s use a form of discovery that is based on broadcast address searching to discover what printers are around.
From things I have read in the past I believe that broadcast address traffic can not be routed from one subnet (green) to another (blue).
I believe that you will need to set up the printer connection URI manually knowing the information about its IP etc.
Where the poster was interested in broadcast access from green to blue for smart thermostats.
I am not certain enough to say it will help your use case but it might be worth a try as according to the wiki page on the addon it requires very little configuration. Just the definition of the two subnets involved.
You know the printer can be accessed via the specific IP so it might be worth a quick test with the addon to see if that helps with the discovery process for the printer. If it does, then it would be good to mention that as a use case in the mDNS addon wiki page.