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Possible Duplicate:
1 Year DHCP Lease

I'm reviewing Azure web role logs and there's output from ipconfig /all

IPv4 Address. . . . . . . . . . . : 10.61.145.37(Preferred) .
Subnet Mask . . . . . . . . . . . : 255.255.254.0.
Lease Obtained. . . . . . . . . . : Monday, September 24, 2012 12:26:00 PM.
Lease Expires . . . . . . . . . . : Thursday, October 31, 2148 6:55:12 PM.

you see, the lease expires in year 2148 but my VM will likely not run for more than one month - when I deploy the new version of my code I first deploy it to new VMs, then switch traffic, then release the new VMs. In general such usage pattern is normal - VMs typically live from several dozen minutes to several weeks on Azure.

I suspect the lease that long will cause problems on the internal Azure network sooner or later.

Is such long DHCP lease okay or is it likely a misconfiguration?

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sharptooth
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  • [You may want to take a look at this similar thread, as well](http://serverfault.com/questions/414660/1-year-dhcp-lease/414709#414709). It's not definitely a misconfiguration (as apparently some guy in that thread wanted to do this on purpose), but it's definitely a bad a idea. – HopelessN00b Sep 25 '12 at 12:16

2 Answers2

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I actually contacted Azure support and they say this is by design so that when a VM is restarted it retains it IP address and lease termination is handled elsewhere.

sharptooth
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This is definitely a misconfiguration. "normal" DHCP Lease time is usually a day but at most a week. The way your DHCP works is almost static leases and your pool will run full in a not to long time.

Flash
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