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Getting Started with IPFire
1

I searched the forum some, but suspect I know not the needed search terms.

I have a fixed lease IP/MAC that has not been used for a while.

And in fact the DHCP server has given the IP to a dynamic lease to a new device.

I’d like to know how I’d find the last time the fixed lease was used, and what steps I should take allow the new device to have the fixed lease.

I’d also like to understand why the DHCP gave the fixed lease to a device with a different MAC address.

Thanks.

2

The fixed lease range is separate from the DHCP range so how is it possible that DHCP gave that fixed IP to another device? I have fixed leases, 10.0.0.1 - .9 and DHCP leases 10.0.0.10 - .49 A device with fixed lease 10.0.0.3 will have that ip forever, used or not used.

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3

Short answer to this ( and similiar questions ):wiki.ipfire.org - DHCP Server
Especially the sections about dynamic and fixed leases.

4

DHCP can give a fixed lease out if the fixed lease IP has been chosen to be within the Dynamic Range. This should not be done but currently IPFire does not stop you from doing that.

If the fixed lease has not been used for a while and the lease time has expired then it can be given to any other computer as the IP is part of the Dynamic Range. That is why they should be kept separate.

I am working on a bug fix to flag up if an overlapped ip is selected.

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5

To clarify: this bugfix only checks settings in the WUI. The behaviour of dhcpcd isn’t altered!

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6

Adolf Belka thank you for answering my question.

Bernhard Bitsch thank you for the RTFM. I had already read it, I read it a second time…that is why I asked the question. But, you couldn’t have known I had read it, or that I have the wiki bookmarked, that is my fault for not mentioning it in my original post. (Or maybe I read the words and couldn’t visualize the answer to my question from them… :pleading_face: )

7

Sorry, if my answer was too short. :wink:
But often there are problems resulting from configurations with non-empty dissections of dynamic and fixed sets.
Was this your problem? You didn’t specify your sets used.

8

Actually, for some reason I thought once an address was moved to the fixed lease list, it was removed from the dynamic list. So, the IP address in question was in the dynamic pool.