Gateways and dynamic IP addresses

  • Hello,

    I am relatively new to pfSense and have inherited a configuration created by someone else. I'm looking for help with an aspect of the configuration that I don't understand.

    We currently have two separate WAN interfaces, each with an associated static IP address. There are also two gateways associated with these WAN interfaces - however, these seem to be linked to the dynamic IP address allocated by the relevant ISP rather than the static IP address.

    In particular, the Gateways panel on the Dashboard displays the Dynamic IP address for each gateway, whilst the Interfaces panel on the Dashboard displays the Static IP address for each interface.

    When I investigated the gateway configuration further, I noticed that the IP address associated with each gateway was set to "dynamic" - however, I've not been able to find any documentation about this configuration option. The documentation for "Gateway Settings" simply says that the Gateway IP address is the actual address of the gateway.

    Is the possibility of setting the Gateway IP address to "dynamic" documented anywhere?

    Also, can anyone explain how or why it was set up in this way? Were the gateway configurations created automatically by pfSense or did they have to be created manually?

    One reason for setting it up this way might be to allow external monitoring of the gateway - according to our ISP, the Static IP address will not respond to ping requests. Does this seem like a plausible explanation? Is there any documentation about configuring gateways in this way?

    Thank you,

    Robert Stroud

  • Banned

    If your GW does not respond to ping, your ISP is an idiot. You MUST edit the GW to either disable GW monitoring, or change the monitor IP to something on WAN that does respond to pings. If your WAN is DHCP, do not touch the dynamic option.

  • Thank you for your reply - my comments about monitoring were a bit misleading because I misunderstood the way in which pfSense monitors gateways. I don't think my ISP is an idiot but it is true that our gateway does not respond to pings on its static IP address - for this reason, an alternate monitor IP address of has been set for the gateway.

    However, my real question is about why the gateways have been set up with dynamic IP addresses rather than static IP addresses, and whether there is any documentation about setting the gateway IP address to  the undocumented value of "dynamic", which is clearly not a valid IP address.

    To explain our setup, we have two WAN interfaces implemented as PPPoE connections to ADSL modems in bridge mode from separate ISPs, two gateways that are configured to use the undocumented "dynamic" value for the gateway IP address, and two static routes via the gateways that enable us to reach the private networks to which each ADSL modem is connected.

    We're planning to replace this with a single connection via a Bonded ADSL Gateway, but as preparation for the new network setup, we're trying to understand how the existing network configuration works and why it has been set up in the way it has…

    Do you always need to create gateways if you have multiple WAN interfaces or do you only need them if you want to set up a gateway group? Or do you need them in order to set up static routes?

    Any comments or insights would be appreciated.

    Thank you,


  • Banned

    Dynamic is dynamic is dynamic because it's dynamic. You are welcome to grep the relevant code. It's autogenerated gateway. What "documentation" you need? When it ain't static, it's dynamic. It could be called "bazooomblahbleh" instead; doesn't matter. Do NOT touch that thing.

  • Thank you for your reply - I know the difference between a dynamic IP address and a static IP address. My question is about why my gateway is configured to use a dynamic IP address when my ISP provides me with a static IP address.

    As for the value "dynamic" not being documented, it's not documented - I mention this is passing in case someone wants to fix the documentation. Code is not documentation.

  • Banned

    Because the code lacks AI to know that your DHCP-assigned IP is static…  ::) ::) ::)

  • OK - I agree that there is no easy to deduce whether an IP address is static or dynamic…  :'( :'( :'(

    So let me ask my question in a different way:

    1. Why is the gateway IP address set to "dynamic" rather than the static IP address?
    2. What would break if I changed the gateway IP address to the static IP address?

    Thank you.


  • Banned

    It is set to DYNAMIC because it is NOT STATIC. If you want static, then get a static IP from your ISP and set up your WAN as STATIC instead of DHCP.

  • But it is static - that's the whole point of my question. My ISP has allocated a static IP address for my WAN, so why is my gateway set to dynamic?

  • Banned

    No, it is NOT static when WAN is set to DHCP. Noone knows that your ISP does not change the leases or the GW. Period. Stop setting the WAN to DHCP when you want static. What on earth is so hard to get here?!?

  • I'm sorry, but you are the one who is struggling to understand what is going on here. I appreciate your attempts to help, but you do not seem to have read my question.

    In particular, my WAN interface definitely has a static IP address - I know this and my ISP knows this. Even pfSense knows this.

    Moreover, my WAN interface is not configured as DHCP - it is configured as PPPoE. But that is not relevant here - my question is about the Gateway configuration in pfSense, not the Interface configuration.

    Why is my Gateway configured as dynamic when my WAN has a static IP address?

  • Banned

    Look, everything that is NOT static is DYNAMIC by definition. If you STILL cannot grok this absolutely simple concept, then imagine you have "pppoe" or "dhcp" or whatever "non-static" written there. If you STILL cannot understand, then just move on.

    And for goddamn sake, whether or not your ISP has a static lease for you is COMPLETELY outside the code's knowledge. Ya know, the code won't ring your ISP and ask "does this dude have a static IP plan with you, guys. Since he's having giant issues with seeing a word "dynamic" so I'd like to replace that in the GUI dynamically [pun intended] with a word that doesn't bother him"?

    ::) ::) ::)

  • This thread made my day!!!!

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