<p>force_dhcp_release=true should cause the ip to be released immediately, assuming the relevant optional binary from dnsmasq is installed (it is in the package dnsmasq-utils in ubuntu). If it is set to false then the ips should be reclaimed after a set timeout period (ten minutes by default) via a periodic task in the network worker. If they are not being reclaimed properly then there is definitely a bug somewhere, although I have not seen this happening recently myself.</p>

<div class="gmail_quote">On Jun 23, 2012 6:14 PM, "Lars Kellogg-Stedman" <<a href="mailto:lars@seas.harvard.edu">lars@seas.harvard.edu</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
> can you try with the flag:<br>
> force_dhcp_release=false<br>
<br>
It turns out I already had force_dhcp_release set to False.<br>
<br>
I've opened <a href="https://bugs.launchpad.net/nova/+bug/1017013" target="_blank">https://bugs.launchpad.net/nova/+bug/1017013</a> on this<br>
issue.<br>
<br>
--<br>
Lars Kellogg-Stedman <<a href="mailto:lars@seas.harvard.edu">lars@seas.harvard.edu</a>>       |<br>
Senior Technologist                                | <a href="http://ac.seas.harvard.edu/" target="_blank">http://ac.seas.harvard.edu/</a><br>
Academic Computing                                 | <a href="http://code.seas.harvard.edu/" target="_blank">http://code.seas.harvard.edu/</a><br>
Harvard School of Engineering and Applied Sciences |<br>
<br>
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