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Curdasss
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DHCP reservation

So here's an interesting question. How do you guy's handle DHCP reservations of your VM's with DRS enabled. I know how to set the MAC address statically but how do you go about managing all of the MAC address of your VM's? Every time I create a new VM I will have to use a MAC address within the range of address of that hasn't been used, which of course is a management issue. Just wondering how other people have managed their VM's in this type of situation.

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Dave_Mishchenko
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The MAC shouldn't change when you use DRS/ HA/ vmotion. It should only change when the path to the VM changes.

http://www.vmware-land.com/Vmware_Tips.html#Net3

http://www.vmware.com/community/thread.jspa?messageID=640809&#640809

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oreeh
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I simply don't use DHCP for servers (and therefore not for VMs) and this problem is the main reason for this.

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MR-T
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2 options I've come across.

1) Excel spreadsheet. (quick and easy to setup).

2) A database with a nice frontend. (requires more skill).

These both work.

As you'll appreciate it's very important to track these as they are issued (and returned) otherwise you risk a conflict.

MR-T
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Does this tool also capture the MAC address?

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esiebert7625
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I'm not sure, I downloaded it a while ago and have been meaning to set it up but have not had the time yet. Here's some more info on it.

http://www.ipanto.com/static/pdf/IpantoProductLiteDiscovery200701.pdf

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MR-T
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Cheers Eric.

It doesn't mention it, but I guess I'll save that test for a rainy day.

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Curdasss
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I setup Ipanto it appears that the Ipanto Discovery edition, not free, will pull the MAC address automatically. However, the freeware edition requires manual discovery and you have to put in the MAC. Not necessarily a bad thing as it will work for keeping track of what MAC address your using and the interface is pretty cool. Thank You guy's for your help.

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msmenne17
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I think I'm missing something here...

What is the purpose for using DHCP Reservations in your VMs?

Each VM has it's own MAC Address (in Windows, type ipconfig /all).

Every VM that is created will have a unique MAC address just as phyiscal servers do.

The process wouldn't be any different than with physical servers.

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Curdasss
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Yes but when you use DRS the MAC address is going to change as it changes physical servers, and of course you don't want your IP's to change, so you need to have them set statically.

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Dave_Mishchenko
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The MAC shouldn't change when you use DRS/ HA/ vmotion. It should only change when the path to the VM changes.

http://www.vmware-land.com/Vmware_Tips.html#Net3

http://www.vmware.com/community/thread.jspa?messageID=640809&#640809

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esiebert7625
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Exactly, the VM never moves from it's original location (SAN), it just changes hosts....

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Curdasss
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I should have thought about that, but for some reason I had stuck in my head that the MAC was actually going to change when DRS switched hosts. I should have known better, but thats why I brought it up here. Thank You

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