06-12-2012 05:04 AM - edited 03-07-2019 07:12 AM
Good day experts.
We have been having a discussion at work regarding IP addressing best practicesfor Inter VLAN routing & default gateways IP addresses.
My question is:
Is it best practice to use the 1st IP address in the block as the Inter VLAN IP address or use the last IP?
Are there pro's & con's for using either?
The same question applies to default gateways etc.
All responses very welcome.
Many thanks.
Rob.
06-12-2012 05:22 AM
Rob,
Really it's 6 of 1 and half dozen of the other. I've seen both ways really. Some people have schemes that use only the last address for their SVIs and then the hosts start from 1 up and then there is the other school of thought that use the 1st address from the SVI and set all of the hosts to use that as the gateway. My particular scheme uses the first address in the block on the SVI and then I set aside 99 static addresses for assigning to hosts. If I have hosts on that vlan that need to be assigned an address via dhcp, I'll start my scope at 100 - 254 (for a class c block).
There's really no pro or cons to one way or the other; just be consistent with it to make it easier on yourself and future admins
HTH,
John
06-12-2012 06:47 AM
I agree i have seen it as .1 or .254 as the gateway for a vlan . No right or wrong , just keep it consistent .
06-12-2012 09:08 AM
I normally use the .1, or the first IP address in the case of a non-full class. I do this so that if I expand from say a /21 to a /20 the defaults do not change and nothing has to be skipped or reserved. Just my two cents worth.
Brent
06-15-2012 12:33 AM
Hi,
Many thanks for all your responses, sorry it took me a while to respond.
I have always used the first ip in the range as I think it is easier when using vlsm etc.
I'm glad to hear that many others do the same.
Once again many thanks.
Rob.
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