One system - two IP's on different subnets?



  • Trying to figure out the best way to do this.

    I have two LAN subnets in my home network, one for home office, one for everyone else.

    I recently bought a nice wireless printer.

    The issue I'm running into is the printer software only sees the printer if it's on the same subnet (at least I think.  Maybe it's finding it via broadcast).  So all the systems on the same subnet 192.168.1.x can see the printer just fine.  But all the systems on my office network 192.168.2.x can't see the printer via it's software.  Now all the IP routing is fine.  I can ping the printer etc, but I think the printer software is limited in some fashion to either only doing discovery on the same subnet or possibly using broadcasts.

    Is there a way to assign the printer a virtual IP on the office LAN (192.168.2.x) so that the systems on that network will be able to find the printer via the printer software?

    And one thing to note, while my printer has both ethernet and wireless, it can't have both on simultaneously (which I was hoping would be the easiest fix).

    Any ideas would be great.

    Thanks,

    Joshua



  • If the printer has a fixed IP, you can just always add it using its IP vs relying on broadcasts or being recognized by home networking or samba or anything.  I'd give it a static IP, type up a quick "How to add this printer" note.  Print that and tape it to the printer.

    I wouldn't have it connect via wired and wireless simultaneously even if some slip-up of manufacturing allowed for it.


  • Netgate Administrator

    You may be able to do that. Alternatively you could try using the IGMP proxy. http://doc.pfsense.org/index.php/IGMP_Proxy
    Can you not print to the printer by it's IP directly?

    Steve



  • For the printer to be able to reply to connections from another subnet, it will need to be able to define a default gateway (the LAN IP of pfSense). If the printer setup lets you specify a default gateway, then great. Add firewall rules on pfSense to allow traffic from the other subnet to the printer IP. Then if you print directly to the printer IP it might work.
    You can also add a name+IP for the printer to pfSense DNS forwarder host overrides (or to whatever local DNS server you may have on your private network). Then you can use the name to access the printer, rather than a "magic" IP address.



  • Magic?  Its not magic. 
    It an IP address.


  • Netgate Administrator

    A reference to this I think.

    Steve



  • Yeah.  (First programming language was Pascal). 
    What what wrong with going straight to C?  :-\

    I like using IPs for things like printers and file shares because it just works so beautifully crossing subnets and VPNs and is simple.
    In the house, everything has a name in DNS but I never use the names.



  • @kejianshi:

    If the printer has a fixed IP, you can just always add it using its IP vs relying on broadcasts or being recognized by home networking or samba or anything.  I'd give it a static IP, type up a quick "How to add this printer" note.  Print that and tape it to the printer.

    I wouldn't have it connect via wired and wireless simultaneously even if some slip-up of manufacturing allowed for it.

    The challenge is it's a big fancy all-in-one printer with a scanner and other junk built-in.  To use the various features, you have to interface to the printer using it's specific software, not the simple IP address printing.  I don't know how it's software is finding the printer, but if it's not on the same subnet, it won't see the printer through the software.  Even after being setup and having the correct IP in the software configuration.  That's why I'm trying to see if I can have a virtual IP on another segment so the printer will appear to be on both segments simultaneously.



  • I've got one like that.  Its a brother DCP 8040.  Old but works so well.  I attach it to a single computer then share the printer via samba and address that computer with IP.  Anyway - goodluck.


  • Netgate Administrator

    Using the IGMP proxy may allow the software to 'find' the printer. I have seen that work with media servers/clients that work in a similar way. Though I've never used a VIP in that manner I can see how it might work, try it.

    Steve


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