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Freeware & Evaluations


Setting up first network

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First, Thanks to Jeff Phelps for the clue about running the VM through the converter. I now have IPAM Express Freeware running on my ESXi 5.5 server. I'm now having problems setting up the first network. I've used the video on Youtube and when I enter I get Invalid network mask. I don't have a lot of network admin experience but I'm trying to learn. What am I doing wrong? This ESXi server is my home server I use for training myself. I do not use it for anything else.
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   /254 is an invalid network mask.  This is known as CIDR (Classless Inter-Domain Routing) notation which defines the number of bits in the address which are the network portion of the IP address.  Therefore, in IPv4, because there are 32 bits in the address, your choices are from /1 through /32.

  For example to scan the entire class C subnet ( through you would specify  With a /24 the 1st 24 bits, 3 octets, are designated as the network portion (192.168.1) and the last octet is the host portion (.0 - .255) of the address.

  If you want to scan the entire class B network ( through then you would use  With a /16 the 1st 16 bits, 2 octets, are designated as the network portion.

  There is a lot more to subnetting and CIDR notation but hopefully this will get you started.

Setting up first network

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Hi Fred,

Did Michael's answer help you?  (Thank you Michael for stepping in!)  The most likely network mask is 24, so you probably need to use  Please let me know if you are still having problems.

Thanks, Allison



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