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Hi,

I have the common issue of instances not getting their ip.
When I start a cirros instance, the output looks like this:

udhcpc (v1.20.1) started
Sending discover...
Sending discover...
Sending discover...
No lease, failing

I've found that during the boot process (while the instance is trying to 
get an ip), if I remove and immediately recreate in the router the 
interface to the subnet in which the instance is located, the instance 
succeds in getting its ip!

I've tested many times, and this method keeps working.
Anyone has a hint about this strange behaviour?

Thanks,

Claudio