A subnetwork, or subnet, is a logically visible subdivision of an IP network. The practice of dividing a single network into two or more networks is called subnetting and the networks created are called subnetworks or subnets.

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Best way to calculate optimal subnet masks for a range of IP addresses? [closed]

I thought I saw a tool like this once upon a time, but can't find it anymore... Anyone know a tool that would take a free range of IP addresses (as in start / end) and calculate a set of submasks ...
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Broadcast traffic on large vlan in numbers [closed]

I'm looking for the magic number of how many clients make sense to have on a single VLAN, before the broadcast traffic becomes a real issue. Preferably, I'd also like to know what a good number of ...
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Manage subnetting from simple router

I want to setup two different subnets in the same physical network with one router, these are my questions: Let's assume I want the first subnet like 192.168.1.0-254 and the second subnet like ...
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Network discovery across VPN and local subnets

This question is about interaction between VPN clients and local machines. I have a simple network on the subnet 10.0.200.0/24.  The router supports VPN.  The router forces the VPN IP pool to be on a ...
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IP Address Subnet [duplicate]

Possible Duplicate: How does IPv4 Subnetting Work? We currently have a: 192.168.3.0/24 Subnet. We are looking to make this subnet larger as we need about 500 IP addresses in the above ...
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need to figure out this subnet mask please is it correct? [duplicate]

Possible Duplicate: How does IPv4 Subnetting Work? The largest subnet has 300 hosts so I am trying to workout the number of host_id bits I require for the mask but I am confused as each ...
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73 views

Routing table connected entries different than interface assigned IP address

I have a HP ProCurve A7102DL router which has eth1 and eth2 interfaces. I currently have eth1 set as my WAN and eth2 as my LAN side. My eth2 has three IP address assigned to it which are A.A.A.1, ...
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ipv6 /96 subnet and ip forwarding

I have a /64 IP subnet and I divided this subnet into /96 subnets in order to use it in the internal and external interfaces of my CentOS machine. The problem is that I can ping an address like ...
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Unable to access different subnet

Router ip: 192.168.3.1 Windows server: 192.168.3.50 (WLan) and 192.168.2.1 (LAN) PCs: 192.168.2.x I am able to access 192.168.3.50 from laptop (in 3.x network) but unable to access through other ...
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How to configure second non-consecutive subnet on same interface?

I have some servers on the public network of my isp, say 192.168.2.0/24. Now my provider gives me additional ip addresses, but unfortunately not in a subsequent range of my first network, say ...
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IBM Proventia Firewall Possibly dropping packets between subnets?

I have a network that has 3 subnets, 10.1.4.0/24, 10.1.5.0/24, 10.1.9.0/24. They are all routed using an IBM Proventia Firewall. The firewall is fairly straight forward and everything seems to be ...
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Best Approach for subnetting/VLANing traffic?

Our network is currently setup with no subnets or VLANs. We are looking at going to VoIP so this needs to change before VoIP is installed. I believe that we want to use VLANs to separate Voice and ...
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Customer site is out of IP addresses, they want to go from /24 to /12 netmask… Bad idea?

One of my client sites called to ask me to change the subnet masks of the Linux servers I manage there while they re-IP/change the netmask of their network based on a 10.0.0.x scheme. "Can you change ...
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Can I use the CLI to reset an IP address from a different subnet?

I'm working with a small office network which has fifteen devices on 192.168.2.x. They want to add a print server to the network. Simple enough, except that the print server seems to think it's ...
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PowerConnect 3548p SNTP and web interface not working

I have been unable to get SNTP and access to the web interface working properly on a Dell PowerConnect 3548p. In the logs, this message appears over and over again: 04-Jan-2000 20:19:29 ...
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705 views

Windows 2008 R2 DHCP Overlapping Scopes

We are trying to troubleshoot a scope overlap problem. We have multiple device types we wish to give all different ranges of a 16 bit subnet. IE. X device we wish to give 192.168.2.1-192.168.2.254/16, ...
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why I can not access a client on different sub net mask? [duplicate]

Possible Duplicate: How does IPv4 Subnetting Work? My computer is on a domain netowrk (joined as domain member) with IP of: 192.168.0.x (DHCP from the DC. I am trying to RDP to a computer ...
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Sonicwall routing between multiple subnets on multiple interfaces

As shown by the network diagram below, I have two completely separate networks. One is being managed by a Sonicwall NSA 220, the other by some other router (the brand is not important). My goal is to ...
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VPN into multiple LAN Subnets

I need to figure out a way to allow access to two LAN subnets on a SonicWall NSA 220 through the built-in SonicWall GlobalVPN server. I've Googled and tried everything I can think of, but nothing has ...
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296 views

Same network subnet across T1 or T3 leased lines?

Suppose I have a bunch of facilities, each with a /16 network under the 10.0.0.0/8 private address range. For example, my head office is 10.0.0.0/16, and we have two branches 10.1.0.0/16 and ...
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Is this IPv4 and subnet combination public or private? [duplicate]

Possible Duplicate: How does IPv4 Subnetting Work? I thought I understood this but I am momentarily confused. Here is an example: Are all IPv4 addresses from 192.168.0.0 to 192.168.255.255 ...
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DHCP for Multiple Subnets

So this is the current setup - essentially I would like to get my DHCP server, serving DHCP requests for two seperate subnets. Netgear DG834G acting as a modem connected to a Sonicwall Pro 2040. X0 ...
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How to use 2 subnets on one network

I have some servers at a colocation. They've given us an IP range, subnet and gateway. Now we have run out of IP addresses and they've given us a new range of IPs but with a different subnet and ...
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Multicast in private LAN with different subnets

after i read Multicast IP Addresses and Multicast accross the subnets I am confused. Configuration: I have two devices in the same network. They may not be in the same Subnet, but ...
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Branch office MPLS connection with 2 different subnets

We had VOIP phone service and an MPLS connection between our main office and a branch office installed recently. The genuis who set things up created an internal network at the branch office using ...
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Can't start eth1 and dhcp on debian wheezy

What I want: eth0 is connected to internet and has a static IP-address. eth1 connected to internal network and be a dhcp server for subnet. But I can't get eth1 to work. Error: $ ifup eth1 ...
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Reach pc in the same network but a different subnet

PC 1 in subnet - 192.168.1.x PC 2 in subnet - 192.168.2.x Is it possible to access one pc from the other by its IP address without special router config? related: How to reach a device on a ...
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A NAT Experiment

I have a Linux box that am using as a router. The box's 'WAN' connection is actually another LAN (the primary LAN). I am trying to use my box/router to create another LAN (the secondary LAN). The ...
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Routing between subnets on different vlans connected by a router/firewall

I have two networks that I'd like to connect with a router/firewall to filter traffic between the two. One network is on a public subnet, let's say 64.22.12.192/27 and the other network is on a ...
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Is it reasonable to put all printers to another subnet?

I have a network of about 90 PCs and about 25 network printers. In near future i will promote one server to DC. However, now PCs on my network have static IP addresses. It is a real mess now with ...
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Allow 2 different subnets to have access to the internet but not each other [closed]

How would I go about getting say 10.0.1.100 and 10.0.0.100 to both have access to the same internet, but not see each other. My Topology can change to make this happen. Currently I have a ...
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Access virtual host of another computer in same network

I made a PHP/MySQL app in my desktop that I access using Apache vhosts (XAMPP). In my host file I added 127.0.0.1 myapp so all I have to type in my browser is http://myapp. How can I access this same ...
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How does IPv6 subnetting work and how does it differ from IPv4 subnetting?

This is a Canonical Question about IPv6 Subnetting. Related: How does IPv4 Subnetting Work? I know a lot about IPv4 Subnetting, and as I prepare to (deploy|work on) an IPv6 ...
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IPTABLE & IP-routed netwok solution for HOST net and VM's subnet

I've got ProxmoxVE2.1 ruled KVM node on Debian and bunch of VM's guests machine. That is how my networking looks like: # network interface settings auto lo iface lo inet loopback # device: eth0 auto ...
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WAN and LAN setup for IPv6

We just got a IPv6 /48 range (a gateway and an IP address) for our company, but I'm unsure about how to set it up. We use FreeBSD 8.4 (pfSense 2.1) as a router/firewall. Currently we have IPv4 setup ...
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IPcop Multiple WAN Subnets

We have an IPcop firewall and have had no issues with it. We've had a block of 10 IP addresses from our colocation provider and have been able port forward from those to internal servers as needed. ...
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smaller CIDR network on larger Class C network

I have a network: 192.168.31.0/24 and computers on the network have static IPs 192.168.31.* I'd like to segregate 5 of those computers (say 192.168.31.201 - 192.168.31.205) and put them behind a ...
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486 views

'IPv6' Newbie with IPv6 address assigment

I am new to IP v6 and I am looking to translate some existing private IPv4 addresses into v6 address assignment. Can someone please help me to answer/explain the questions below? If I have an v4 ...
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Counting subnets [closed]

I'm reading about subnetting but have problems with these topologies. The book says that network1 has 4 subnets and network2 has 12 subnets. But I count only 11 subnets in netork2 ? If there is a ...
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How drastically can a public IP change?

On ISP level, is it commonly limited to some subnet mask? Is it possible or rare for an ISP to randomly change an IP's first 2 bytes? Just as a bit of backstory, I'm trying to deter users from ...
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OpenVPN subnet routing on openSuSE

First off: I have looked all over for a solution to this, but couldn't find anything. How can I make OpenVPN's subnet accessible to my LAN? BACKGROUND INFORMATION: I have an openSUSE 12.1 box that ...
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2answers
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KVM with one host IP and a different subnet for machines

I've already setup a KVM host with proper IP configurations, but my host had me create DHCP and use that to assign the IP's to the machines. I want to see if there's an easier way to do it (or ...
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How to route two subnets to the internet via a linux box acting as router and proxy

I have a linux box that acts as router, DHCP server, and proxy. On my LAN side I need two subnets to have enough IPs: 192.168.100.0 - 192.168.101.255 - is the range I need. Both subnets must be able ...
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multiple physical interfaces with IPs on the same subnet

I have a linux box with 9 NICs on it, and I want eight of them to have unique addresses on the same subnet, e.g.: ifconfig eth1 192.168.123.1 netmask 255.255.0.0 ifconfig eth2 192.168.123.2 netmask ...
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Can't ping D-Link AP From different subnet

I have two different subnets set up on my network (say 10.10.10.* and 10.10.12.*). I am having difficulty pinging a D-Link access point (was a router, now configured to be an AP) located on subnet 1 ...
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dhcp same subnet different vlans

I want to setup my work's network so that all wireless clients get assigned a certain IP range but are on the same subnet as the other network devices. Currently I'm running dnsmasq for DHCP and DNS ...
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One ISP, two switches, two subnets

A quick overview of my environment: Network A: One gateway/DHCP server connected to multiple ISPs and connected to the switch One Netgear GS748T 48 port switch (and a few trunked switches for the ...
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3answers
398 views

IP Address Planning for our Network

We have a /24 IP Address range for PCs containing 240 allocated addresses at the moment. Our company is planing for expansion of another 50 PCs, our existing IP range is 192.168.8.0/24 Do we add on ...
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RRAS with DHCP when the IP pool is on a different subnet

I run a small business network and the last couple of days I have been setting up some equipment to add VPN capabilities to our network. I've got the following set up: Windows 2008 R2 with RRAS - ...
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Number of Subnets and total hosts [duplicate]

Possible Duplicate: How does Subnetting Work? Can someone please tell me what does this term means "A Class C network with 10 subnets" What exactly is 10 subnets? I know a subnet is ...