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    Do you use dhcp reservations?

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    • maverickwsM
      maverickws
      last edited by

      Poll seems 7 to yes 0 - 0 by when I voted.

      Yes we do use reservations. For everything. Only known Macs are allowed to connect to networks.
      There is one network without reservations, the gust network.

      Now-a-days there are devices that cloak their real MAC address, so sometimes what we do when a new device is introduced to the home network (we don't exchange phones that much) we temporarily allow any client to connect, then make the reservation.

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      • AndyRHA
        AndyRH
        last edited by AndyRH

        I only use static when I have to, gateway, Proxmox, Piholes.
        Anything that I care about the address is a DHCP reservation, such as AP, computers, servers, cameras.
        Other is just DHCP, I do not care what IP a phone has. The DHCP scope is small, I think it is 30 addresses.
        VLAN666 (Alexia) is isolated and is straight DHCP, I don't manage the evil network... 😈

        o||||o
        7100-1u

        bmeeksB 1 Reply Last reply Reply Quote 0
        • bmeeksB
          bmeeks @AndyRH
          last edited by bmeeks

          @AndyRH said in Do you use dhcp reservations?:

          I only use static when I have to, gateway, Proxmox, Piholes.
          Anything that I care about the address is a DHCP reservation, such as AP, computers, servers, cameras.

          Not trying to be argumentative, and don't want to start a war ... just asking why choose reservation over static when you want a given device to have a given IP.

          To me, it is easier in such situations to use a static IP assignment. That way, should I replace the physical device, I simply configure it with the same static IP.

          If I use a reservation, I have to find the new MAC address for the replacement device, then go edit the DHCP reservation, then either reboot the device or renew its lease so it picks up the proper IP address. It just seems like extra work. Carving out a section of the IP space for static assignments seems easier. For example, in a /24 netblock I might carve out .1 through .29 for static assignments (more or less depending on anticipated needs). And in the DHCP configuration in pfSense, you can't assign a reservation from your DHCP scope anyway. It must be a separate IP address not covered in the active DHCP scope pool. At least in Windows you can arbitrarily choose any IP within the scope to be a DHCP reservation.

          AndyRHA maverickwsM A 3 Replies Last reply Reply Quote 0
          • AndyRHA
            AndyRH @bmeeks
            last edited by AndyRH

            @bmeeks No war needed. If I change PiHoles, which has happened, I update DHCP and the changes are propagated. Same thing with NTP.
            When I changed physical firewalls, it was great. I just put in the new settings and waited a day then turned off the old one.
            Either way is valid.

            o||||o
            7100-1u

            bmeeksB 1 Reply Last reply Reply Quote 0
            • maverickwsM
              maverickws @bmeeks
              last edited by

              @bmeeks said in Do you use dhcp reservations?:

              just asking why choose reservation over static when you want a given device to have a given IP

              Mind elaborating the difference between "reservation" and "static" in your perspective. afaik there is none.

              bmeeksB 1 Reply Last reply Reply Quote 0
              • bmeeksB
                bmeeks @AndyRH
                last edited by bmeeks

                @AndyRH said in Do you use dhcp reservations?:

                @bmeeks No war needed. If I change PiHoles, which has happened, I update DHCP and the changes are propagated. Same thing with NTP.
                When I changed physical firewalls, it was great. I just put in the new settings and waited a day then turned off the old one.
                Either way is valid.

                Agree that either way is valid. It is a lot based on personal preference.

                I came from a Fortune 500 network environment where we managed probably 50,000 devices or more (nearly 30,000 of those were employee desktop PCs and laptops). We made extensive use of Windows DHCP dynamic DNS updates to register those employee devices so the internal Help Desk could find them quickly by name instead of having to talk the user through identifying the particular IP address they had at the moment. We named the devices using a variation of the employee's network login ID.

                We also used small static IP blocks carved out of the various IP subnets. In those static blocks is where we put things like core switches, network closet switch stacks, and most servers.

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                • bmeeksB
                  bmeeks @maverickws
                  last edited by bmeeks

                  @maverickws said in Do you use dhcp reservations?:

                  @bmeeks said in Do you use dhcp reservations?:

                  just asking why choose reservation over static when you want a given device to have a given IP

                  Mind elaborating the difference between "reservation" and "static" in your perspective. afaik there is none.

                  Reservation is a DHCP construct based off of the client's MAC address. So anytime the hardware changes (new device or replace the network card), the MAC changes and you need to edit the reservation in the DHCP server. With static IP, I simply type in the desired IP address in the client's network setup screen. Both yield the same end result -- a given client gets a particular fixed IP address. What's different is exactly how you get there (at least that's how I define it).

                  maverickwsM 1 Reply Last reply Reply Quote 0
                  • maverickwsM
                    maverickws @bmeeks
                    last edited by maverickws

                    @bmeeks I don't think it was ever discussed in this topic "client-side configurations".

                    Truth be told, there is no reference on the pfSense software to DHCP Reservations (may be wrong but I really don't think there are).
                    When you go to DHCP Server you have an option to add a static entry. I believe it's a colloquialism where people are using reservation instead of static entry. You can't add "reservations" on pfSense, at least not by that nomenclature.

                    bmeeksB 1 Reply Last reply Reply Quote 0
                    • bmeeksB
                      bmeeks @maverickws
                      last edited by bmeeks

                      @maverickws said in Do you use dhcp reservations?:

                      @bmeeks I don't think it was ever discussed in this topic "client-side configurations".

                      Truth be told, there is no reference on the pfSense software to DHCP Reservations (may be wrong but I really don't think there are).
                      When you go to DHCP Server you have an option to add a static entry. I believe it's a colloquialism where people are using reservation instead of static entry.

                      The wording can be confusing. I like to think of it as a reservation because you are reserving that IP address in the mind of the DHCP server, but only for a client whose MAC address matches the one you enter in the static assignment setup.

                      The other way, when I say "static", is on the actual client device I configure the network for "static IP" and not DHCP, and I manually type in the address and subnet I want that client to use. I realize that in the world of IoT, there may be devices that can only do DHCP, and if that is the case then you would need to use the DHCP reservation route to have a known, fixed IP address on the device.

                      So, to clarify, when I say "reservation" I am thinking of an entry in the DHCP server's configuration where I link a particular MAC address with a particular IP address. When I say "static", I am thinking of the situation where the client device is NOT using DHCP and I instead enter the IP information directly into the client manually. Been doing this sort of thing for a little over 40 years, and that's just the way I learned way back when.

                      maverickwsM 1 Reply Last reply Reply Quote 1
                      • M
                        mer
                        last edited by

                        Yep. Been using them for a long time on the home network.
                        Makes it very easy to distingush "normal" devices from guests.
                        Since pretty much everything defaults to doing DHCP you wind up managing everything from a single place.

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                        • maverickwsM
                          maverickws @bmeeks
                          last edited by maverickws

                          @bmeeks got it.
                          I figured it was just some nuance of speech but wanted to clear it out just to make sure. Personally I most times call them "static mappings" or "arp mappings".

                          Also I believe there is a situation here, if I'm wrong please someone correct me but

                          pfSense allows a static mapping from many to one. This is, you can have several static entries using different MACs and the same IP address.
                          Now I am not sure because I hardly ever selected this option, but I figure when you select the option to have that
                          ARP Table Static Entry maybe then it is a reservation? Again, not sure on this one.
                          But in the true concept of the term, as it allows several entries for the same IP, it hardly ever is a reservation.
                          Also, by the way pfSense works, static mappings only exist outside the DHCP dynamic range, so an IP on the range "static" wouldn't go to the dynamic attributions.

                          johnpozJ 1 Reply Last reply Reply Quote 0
                          • Bob.DigB
                            Bob.Dig LAYER 8
                            last edited by Bob.Dig

                            I use it, even with IPv6.
                            (One person doesn't like this)

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                            • KOMK
                              KOM
                              last edited by

                              I don't use reservations at home or at the office. For me the only benefit would be easier renumbering, and that's something I haven't needed to do in the 20+ years I've been at this company. I report directly to the owners and they want to be able to do whatever they want when they want including weekends and evenings when I'm not around. I appreciate the security aspects but the owners don't like security getting in the way of their convenience.

                              Sergei_ShablovskyS 1 Reply Last reply Reply Quote 0
                              • A
                                azdeltawye @johnpoz
                                last edited by

                                @johnpoz
                                Yes, I rely heavily on DHCP reservations for firewall rules and grouping of similar devices..

                                Does Kea DHCP not allow for static mappings?

                                johnpozJ 1 Reply Last reply Reply Quote 1
                                • A
                                  azdeltawye @bmeeks
                                  last edited by

                                  @bmeeks said in Do you use dhcp reservations?:

                                  To me, it is easier in such situations to use a static IP assignment....

                                  Maybe in some cases. However, many dumb IOT devices are 'hardwired' for DHCP.

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                                  • M
                                    MoonKnight @johnpoz
                                    last edited by

                                    @johnpoz

                                    Yes I use lot of DHCP Static Mappings all over my VLAN's :)

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                                    • johnpozJ
                                      johnpoz LAYER 8 Global Moderator @azdeltawye
                                      last edited by

                                      @azdeltawye said in Do you use dhcp reservations?:

                                      Does Kea DHCP not allow for static mappings?

                                      It does, but does not register them in unbound for dns as of yet.

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                                      • ahking19A
                                        ahking19
                                        last edited by

                                        Yes, for all my home VLANs except the Guest one.

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                                        • johnpozJ
                                          johnpoz LAYER 8 Global Moderator @maverickws
                                          last edited by johnpoz

                                          @maverickws said in Do you use dhcp reservations?:

                                          Personally I most times call them "static mappings" or "arp mappings".

                                          Why I called it out and hope make clear what I was talking about.. The static mapping term seems to be newer wording.. Us old farts, at least in my part of the world use reservation - because that is what they are, they are reservation for that mac to get this specific IP.. Kind of like when you make a reservation at a restraunt for table by the window..

                                          But maybe it also just regions of the world use different terms?

                                          That is another thing that is curious ;) maybe I could start another poll - hehehe

                                          static mapping and arp mapping don't make a lot sense to me... Because that is not what it is, its a "reservation" on the dhcp server to give client X ip Y..

                                          And unlike the Seinfeld episode, a dhcp server normally knows how to hold a reservation ;)

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                                          • bmeeksB
                                            bmeeks @johnpoz
                                            last edited by bmeeks

                                            @johnpoz said in Do you use dhcp reservations?:

                                            Us old farts, at least in my part of the world use reservation

                                            Welcome to the official pfSense old farts club 🙂. We can be the charter members!

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