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    Any precautions when changing LAN from /24 to /23 on CARP setup.

    Scheduled Pinned Locked Moved General pfSense Questions
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    • K Offline
      k22
      last edited by

      Hello -
      I have two units in a CARP setup. I need to change a LAN network from /24 to /23. Any precautions I should take or is this fairly straightforward?

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      • DerelictD Offline
        Derelict LAYER 8 Netgate
        last edited by

        What is your LAN subnet currently?

        Chattanooga, Tennessee, USA
        A comprehensive network diagram is worth 10,000 words and 15 conference calls.
        DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
        Do Not Chat For Help! NO_WAN_EGRESS(TM)

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        • K Offline
          k22
          last edited by

          10.10.11.0/24
          I want to change to 10.10.10.0/23.

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          • DerelictD Offline
            Derelict LAYER 8 Netgate
            last edited by

            Yeah, that gets kind of messy. What are your CARP/interface addresses? What is your DHCP Pool? Any other statics/DHCP static mapping ranges?

            (This is why I always put my stuff on CIDR boundaries like 8, 16, 24, 32 instead of, say, 11.)

            Chattanooga, Tennessee, USA
            A comprehensive network diagram is worth 10,000 words and 15 conference calls.
            DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
            Do Not Chat For Help! NO_WAN_EGRESS(TM)

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            • K Offline
              k22
              last edited by

              CARPs are 10.10.11.2 and 10.10.11.3.
              My pool is 10.10.11.12 - 10.10.11.250.
              I have some statics 10.10.11.5 - 10.10.11.10.

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              • DerelictD Offline
                Derelict LAYER 8 Netgate
                last edited by

                OK so those are going to be in the middle of your new range so you are going to have to either change them or do multiple DHCP pools.

                You need to realize that the network and broadcast addresses of all your clients are going to be mismatched.

                You might want to, in advance, temporarily shorten your DHCP lease time to minimize how long your clients have the old settings.

                Is pfSense your DHCP server? Is it configured in HA mode?

                Chattanooga, Tennessee, USA
                A comprehensive network diagram is worth 10,000 words and 15 conference calls.
                DO NOT set a source address/port in a port forward or firewall rule unless you KNOW you need it!
                Do Not Chat For Help! NO_WAN_EGRESS(TM)

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                • K Offline
                  k22
                  last edited by

                  Shortened the dhcp lease per suggestion and made the changes. Everything went smoothly. Many thanks for all the help.

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