Questions

IP Address and IP Ranges Resulting from Supernetting /24 to /23

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IP Address and IP Ranges Resulting from Supernetting /24 to /23

dradow
I would like to increase my IP address range past 254. My current set up is 192.168.2.1/24, and I have a few questions regarding increasing IP addresses by supernetting.

1. I know that I can double my IP addresses if I configure the submask to be 255.255.254.0, but what would the advantage of configuring the submask to that versus opening more ip addresses by changing the submask to 255.255.0.0?

2. When I change my submask to 255.255.254.0, I know I now have 510 ips available, but what does that mean for my IP address ranges?. So my range can be from 192.168.2.1 to 192.168.3.255. However, does it have to be that range? or can I scope it to be 192.168.1.0 to 192.168.2.255? or can I pick 192.168.2.1-192.168.2.225 and 192.168.6.1 to 192.168.6.225?

3. Seems like I might not entirely understand how submasking work. I just know that a submask of 255.255.254.0 allows 2 different numbers for the third section increasing the ip host # from 255 to 510.

Going crazy, PLEASE HELP!


Thanks in advance!
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    gdeangelis

    just remember when you set this up that you will want to be sure your upstream devices are aware of the new network and mask. Also, you can have multiple /24 subnets or a larger address space with a /23 as you noted. There are advantages and disadvantages to both. By increasing your space, you are going to have more broadcast traffic. Depending on what you are trying to achieve, and the hardware you have, you might find it more efficient to add a second /24 network and vlan. Having discontiguous networks (192.168.1.1-254 and 192.168.6.1-254) without vlans (or all in a single vlan) is probably not a good idea on a number of levels unless you have some extra hardware to route it all. Too messy. If you can give a little more detail about what you are trying to accomplish and what you have for hardware, we can go from there.

  • +
    0 Votes
    gdeangelis

    just remember when you set this up that you will want to be sure your upstream devices are aware of the new network and mask. Also, you can have multiple /24 subnets or a larger address space with a /23 as you noted. There are advantages and disadvantages to both. By increasing your space, you are going to have more broadcast traffic. Depending on what you are trying to achieve, and the hardware you have, you might find it more efficient to add a second /24 network and vlan. Having discontiguous networks (192.168.1.1-254 and 192.168.6.1-254) without vlans (or all in a single vlan) is probably not a good idea on a number of levels unless you have some extra hardware to route it all. Too messy. If you can give a little more detail about what you are trying to accomplish and what you have for hardware, we can go from there.