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DNS/DHCP Settings

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  • DNS/DHCP Settings

    Hi all just looking for some advice. we have different iP zones set for WiFi, VPN and Wired.
    Just trying to figure the best way to set the DHCP lease and the scavenging to remove or at least limit the duplicate IP issue we are currently facing.
    Example: someone works from home on VPN in the morning then heads to the office and plugs in. Later they go to a meeting taking their laptop and connect to WiFi. Currently they will have 3 entries in DNS. I'm looking to limit the time that this will cause an issue for us, as I dontthink we can eliminate it fully.

    I'm thinking of creating 2 new zones and and setting scavening/no refresh to 12 hours each and the DHCP lease to 8 hours. May need to do the same with the wired connections too. Will increase traffic, but duplicate IP's is causing the VPN clients to get issues at times.


  • #2
    Re: DNS/DHCP Settings

    Set your wired DHCP leases to a couple of days, if you like. It's not as if those move around, right?

    As for wifi and VPN--if those are on separate DHCP scopes, set those leases to something like 1 or 2 hours. Since a DHCP lease is automatically renewed halfway thru the lease period (and in the background) any time a client disconnects, that now-unused lease will only be in place for an hour at most. As for DNS scavenging, I'd say you don't need to create new zones, just set your current Forward and Reverse zones to both scavenge at something like 8 hours, maybe less. It won't throw out current leases but should keep the orphaned entries clear.

    And there's always changing the scope size(s), assuming you're using private IP ranges (also assuming you're using ipv4).
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