Refresh am I right or cracked?

itdaddyitdaddy Member Posts: 2,089 ■■■■□□□□□□
Okay here goes:

s = subnet bits
h = host bits

If ip subnet-zero is enabled (by default = yes) Then

subnets = 2 ^s

hosts = (2^h)-2

else if ip subnet-zero not enabled Then

subnets = (2 ^s) -2

hosts = (2^h)-2

End If

Conclusion is subnets are not always -2 but host calc is always minus 2?

Is this right? I Know how to calcluate all and subnettings easy. This one rule is fuzzy cause I was taught not to use all 1s and all 0s subnet. I wouldnt use it today but if I was forced to I could. It only affects using the all 1s and all 0s subnet right not the hosts ever right?

But is this logic right dudes?


  • Options
    NuulNuul Member Posts: 158
    It depends, total hosts available does vary with no subnet zero vs without. Since you lose those two networks when you're not using subnet zero you loose the hosts from those too. You look to be talking about hosts per subnet though, so that won't change with or without subnet zero.
  • Options
    itdaddyitdaddy Member Posts: 2,089 ■■■■□□□□□□

    yes right right I mean the host per subnet not total yes..
    hey thanks for the 2nd set up eyes and brain.

    I like to bounce my thoughts on other since I dont have any one who does net engineering around. me thank you ;)

    but yes I agree with what you said...icon_thumright.gif
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