<p dir="ltr">Also you should know that there are three private ranges you can use:</p>
<p dir="ltr"><a href="http://192.168.0.0/16">192.168.0.0/16</a><br>
<a href="http://10.0.0.0/8">10.0.0.0/8</a><br>
<a href="http://172.16.0.0/19">172.16.0.0/19</a> (172.16.0.0-172.16.31.255)</p>
<p dir="ltr">the one you are in is already class A, you don't need to make the broadcast domain that big - flat networks do not scale well.</p>
<p dir="ltr">Better to carve out another /24 block in 10.0 and route between them.</p>
<div class="gmail_quote">On Jan 23, 2014 11:05 AM, "Brian Mathis" <<a href="mailto:brian.mathis%2Bale@betteradmin.com">brian.mathis+ale@betteradmin.com</a>> wrote:<br type="attribution"><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr"><div>Here's some information that may help:<br><br></div>The idea of "Class A, B, C" networks is long gone. In the old days, you could generally think of subnets having those classes, corresponding to netmasks of 255.0.0.0 (class A), 255.255.0.0 (class B), and 255.255.255.0 (class C). This is not strictly correct, but it's good enough for the purposes of this discussion.<br>
<br>In modern times we have moved to "Classless Inter-Domain Routing", or CIDR subnetting. This is what you are indicating when you use the "/" notation on the end of a subnet, like <a href="http://192.168.1.0/24" target="_blank">192.168.1.0/24</a>. The / is not simply a shortcut to save you typing, but indicates that you are actually using CIDR subnets. The / number indicates how many bits are in the netmask, and some of these just happen to match up with the old idea of class-ful networks (/8 = class A; /16 = class B; /24 = class C), but you can have other numbers as well, each one giving you a network with a different number of hosts. You can make a subnet smaller by allocating more mask bits to the subnet (/25), or make larger by using fewer mask bits (/23).<br>
<div><div><br>Here's a good site where you can play with the IP ranges and subnet masks to see how choosing a different CIDR changes your other network parameters: <a href="http://www.subnet-calculator.com/cidr.php" target="_blank">http://www.subnet-calculator.com/cidr.php</a><br>
<br><div class="gmail_extra"><br></div><div class="gmail_extra">Subnetting is done to isolate broadcast domains -- that is -- if a host needs something and it doesn't know who to talk to, it will send out a broadcast packet asking anyone to respond. This happens frequently, and many services on your network can do this. Open up wireshark or tcpdump and you can see that there's probably a lot more broadcast traffic than you think. If you get too many hosts on a network, productive network traffic can get drowned out by the broadcasts, so you want to try to keep subnets to a reasonable size.<br>
</div><div class="gmail_extra"><br><br></div><div class="gmail_extra">Regarding gateway/firewall IP addresses. When a host is talking to another host within the local subnet, they talk directly to each other. However, if a host is trying to talk to someone outside of the subnet, it can't talk directly to it, so it sends the packet to the default gateway and says "you deal with it". The default gateway IP address is just that address set aside within the local network for the gateway to use, and has no other special properties. From a subnet perspective, the gateway IP address is just another host on the subnet.<br>
<br><br></div><div class="gmail_extra">Given your situation, what you are talking about doing is feasible. You can blow up your subnet to a /16, or even just go to a /23, which will give you 510 available addresses. I don't think there's much harm in going to a /16 as long as you don't fill it up, but it's certainly a huge subnet. You don't need to change your gateway IP address (you do need to update the subnet mask on that device), but you need to make sure that you don't accidentally use that IP for other things (such as if you modify your DHCP range).<br>
<br>I think a bigger problem you might have is that since you're out of IPs, it means you have 254 hosts already on one subnet, and you're probably already seeing performance problems because of that. You really need to consider implementing separate subnets instead of making one big one.<br>
<br clear="all"><div><br>❧ Brian Mathis</div>
<br><br><br><div class="gmail_quote">On Wed, Jan 22, 2014 at 10:55 PM, Chuck Payne <span dir="ltr"><<a href="mailto:terrorpup@gmail.com" target="_blank">terrorpup@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">
Guys,<br>
<br>
I need to as a question, I am weak on networking. Every where I have<br>
worked we had a network guy, so I didn't have to deal with this much<br>
<br>
Currently were I work I am about to run out of ip's, for now every is<br>
<a href="http://192.168.11.0/24" target="_blank">192.168.11.0/24</a> lets say<br>
<br>
We are using a Class C ( <a href="http://10.11.0.0/24" target="_blank">10.11.0.0/24</a> 254 Hosts Usable ), our head<br>
program was us to move to a class B ( <a href="http://192.168.0.0/16" target="_blank">192.168.0.0/16</a> 65534 Host Usable<br>
)<br>
<br>
My question is this, I currently have a firewall that is my gateway,<br>
it is <a href="http://192.168.11.254/255.255.255.0" target="_blank">192.168.11.254/255.255.255.0</a><br>
<br>
If I change all the ip's even the gateway netmask from 255.255.255.0<br>
to 255.255.0.0 with it work with my gateway? Then can I use any ip on<br>
the 192.168.0.0 range with my gateway.<br>
<br>
So for example I set up the the following to use<br>
<br>
<a href="http://192.168.10.0/255.255.0.0" target="_blank">192.168.10.0/255.255.0.0</a><br>
<a href="http://192.168.11.0/255.255.0.0" target="_blank">192.168.11.0/255.255.0.0</a><br>
<a href="http://192.168.12.0/255.255.0.0" target="_blank">192.168.12.0/255.255.0.0</a><br>
<br>
I am currently reading a few books, but they aren't answering my question.<br>
<br>
I like to be able for ip to work together with the one fireway. By the<br>
way, I know that <a href="http://192.168.0.0/24" target="_blank">192.168.0.0/24</a> is a private range for a class c, and<br>
what I am talking would be better with <a href="http://10.0.0.0/16" target="_blank">10.0.0.0/16</a>, but I am use to<br>
working with 192.168.0.0.<br>
<br>
<br>
<br>
--<br>
Terror PUP a.k.a<br>
Chuck "PUP" Payne<br>
<br>
<br>
</blockquote></div><br></div></div></div></div>
<br>_______________________________________________<br>
Ale mailing list<br>
<a href="mailto:Ale@ale.org">Ale@ale.org</a><br>
<a href="http://mail.ale.org/mailman/listinfo/ale" target="_blank">http://mail.ale.org/mailman/listinfo/ale</a><br>
See JOBS, ANNOUNCE and SCHOOLS lists at<br>
<a href="http://mail.ale.org/mailman/listinfo" target="_blank">http://mail.ale.org/mailman/listinfo</a><br>
<br></blockquote></div>