DHCP Leases And Cleanup

Routers
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1

Hey all,
I am having issues with the route10 and its ability to clean up leases in DHCP. Currently, my site is showing 149 devices… Which is highly inaccurate (120 are inactive). I just went through and cleaned up about 50 of them. Reloaded the page… and they all came back.

What is happening with this? There is no mass delete of disconnected/offline leases. My Lease time is set for the default 1 day.

What can I do?

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Before you do what I’m about to suggest, I might recommend doing a screen recording of that reloading behavior and kicking off a support request to make sure that gets looked at further: https://help.alta.inc/hc/en-us/requests/new

But anyway! Should be able to clear out the DHCP leases from the terminal since I don’t believe that’s been implimented yet in the controller. Should be something like the following:

  • Shift+click on the router name in the controller to open the terminal
  • If we want to remove all the DHCP leases (for the sake of simplicity), this command should do it rm /cfg/dhcp.leases
  • Could also manually edit that file with nano /cfg/dhcp.leases
  • Then the dnsmasq service needs to be restarted /etc/init.d/dnsmasq restart or the router as a whole could be rebooted

If it’s excess DHCP leases causing the issue then that should hopefully clear them out.

I might also suggest lowering the DHCP lease time to something like 8 hours (28800). Or even lower if it’s a network where lots of devices come in and out. I’ve often found Apple recommendations for their client devices pretty decent in this regard: Recommended settings for Wi-Fi routers and access points - Apple Support

Hope that helps!

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Might have been a fluke… I stepped away form it and came back a few days later (I did lower my DHCP lease time from the default) and its showing the correct device count + allows me to remove old VM’s now.

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