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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Routing between two routers with static routes

I have a Draytek 3200 router and a pfsense rackmount router that I am trying to get to route to each other. I have a subnet on each router and a subnet for the link between, as shown here: As it ...
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15 views

Routing is disabled for LAN users while choosing all-net for IPSec tunnel

I have VPN with L2TP/IPSec server and tunnel configured. When I choose all-nets 0.0.0.0/0 to allow connection from any computer in the world, all LAN users with subnet 10.0.0.0/8 are disconnected from ...
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Access HTTP Server in the Same Subnet [on hold]

I am trying to access http server running my laptop to my android mobile. But it's not accessible. But the server is accessible from other laptops. Firewall is open for the port 8080. Laptop Ip ...
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2answers
33 views

Combining two subnets with same default gateway

This is the current situation: Subnet 1: 192.168.1.x (255.255.255.0) with default gateway on 192.168.1.1 Subnet 2: 192.168.90.x (255.255.255.0) without any gateway (no internet access) -> all ...
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52 views

how is a subnet mask used by a pc? [duplicate]

I understand how a router uses a subnet mask to determine whether to send a packet to the local network or to the WAN. But I am still fuzzy on how the pc uses the subnet mask. When an application on a ...
0
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0answers
39 views

Subnetting and VLANs for Multiple Buildings Strategy

Curious for a little feedback on how others do this. A site I'm looking at has multiple buildings connected by fiber and each is on their own subnet. 192.168.0.0 - Building 1 - VLAN10 192.168.1.0 - ...
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1answer
203 views

RRAS 2012R2 NAT with isolated subnets

I'm trying to find a solution for this problem for many weeks I hope someone can help me. I have a rather simple network: Windows Server 2012R2 with multiple NICs A few subnets (VLANs) with DHCP's ...
0
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1answer
28 views

Locating an AWS S3 physically in a private subnet (like RDS)

Similar to how an RDS instance requires you to pick the specific subnets (which can be in a VPC's private subnet), can AWS S3 stores also be physically located in a VPC's private subnet?
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3answers
951 views

How to access devices with static IPs on different subnet than router?

I have a SonicWall TZ100, firmware SonicOS Enhanced 5.8.1.13, with a static subnet of 10.0.6.0/24 on X0. Ports X2-X4 are port shielded to X0. On ports X3 and X4 I have two devices that were moved from ...
0
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2answers
30 views

Is a “bridging device” required to join two networks?

We're considering two NBN fibre connections to the Internet (NBN is a fibre connection for those of you not living in Australia), with each connection having it's own subnet. The first connection's ...
0
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2answers
190 views

Interesting network design with advanced sub-netting issues

Two clients share a town house together; Each has "X" number of floors. One has the top few the other the bottom. The issue is there are a number of IP security cameras, some private to each network ...
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14 views

Can foreman handle nested subnets?

In Foreman 1.8 one can manage subnets through the web-interface at Infrastructure > Subnets. However, when I add a /24 (e.g. 10.10.0.0 with a subnetmask of 255.255.255.0), I cannot add anything less ...
0
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1answer
69 views

Make Asterisk to serve another subnet

I have server with Linux Ubuntu 12.04. It has two subnets - 192.168.0.1(eth0) and 192.168.1.1 (eth1). There is an Asterisk server (IP PBX) connected to first subnet, lets say it has IP address ...
2
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4answers
4k views

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 ...
0
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2answers
81 views

First and last IP address of the network 192.168.176.0/23 (subnet 23) [duplicate]

Let's have the following address of the network: 192.168.176.0/23. What are the first and last IP addresses of this network? Following this answer http://serverfault.com/a/327782/288201 I assume ...
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12answers
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Is it better to use the 192.168.x.x or 10.x.x.x address range for a small business network?

For best performance and ease of management, is it better to use 192.168.x.x or 10.x.x.x range of addresses for a small (<50 PCs) business network? This would correspond to a subnet of 255.255.0.0 ...
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2answers
46 views

Iptables doesn't forward ssh access to instance under a public subnet

I have the following scenario: 1 - A bastion (NAT) instance which I use as a gateway to forward ssh access to all my private instances (using iptables) [Private IP: 10.10.1.10 Public IP: ...
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0answers
24 views

Security implications of wide WAN subnet

I have a server at OVH and say my public IP adress is xx.xx.xx.81 and the gateway is at xx.xx.xx.254. To reach the gateway, I need pfSense to be configured static WAN IP with xx.xx.xx.81/24, i.e. the ...
0
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2answers
921 views

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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2answers
1k views

MAC OS X Server Lion - how to join two subnets?

I've got two routers connected to two different providers. I also have Mac OS X Lion server connected to both of them, so it looks like this: [INTERNET] [INTERNET] | ...
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2answers
190 views

pfSense: How to add a second WAN subnet for dummies

Can anyone point me to info on what to change on a pfSense device for a 2nd subnet on a single interface? My colo provider has allocated a /29 subnet to me of which I can use 3 IP addresses (for some ...
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1answer
32 views

Linux kernel behavior when dealing with colliding subnets

I'm using openconnect to connect to my office VPN. They push some pretty crappy/aggressive routing rules allocating ALL of the private IP address spaces >.< After I connect to my office VPN, my ...
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1answer
36 views

Utilizing A Secondary IP On A NIC In A Windows Cluster

RELEVANT INFORMATION I have a windows cluster with 3 nodes in it... Node1 Node2 Node3 I have 4 NICs on each node... NIC1_Host NIC2_Virtuals NIC3_Cluster_HB NIC4_Live_Migration This is the ...
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1answer
83 views

AH00526 - apache 2.4 require ip range

I'm using FreeBSD 9.2-RELEASE-p5 w/ apache24-2.4.12 package: [root@j ~]# uname -a FreeBSD X 9.2-RELEASE-p5 FreeBSD 9.2-RELEASE-p5 #0 r265974: Wed May 14 07:57:04 PDT 2014 ...
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2answers
64 views

setting up default-gateway on a router

So I've got this weird assignment, where each branch office has to be able to access the main office (and Internet) through a serial connection. Since switches don't have a serial connections ...
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3answers
1k views

Is it possible to SSH access a server with a misconfigured subnet?

We have a server where one of our engineers misconfigured the subnet and now we are locked out of this server and the only access that I know of would work is a serial console from IDC (it means ...
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6answers
3k views

Linux Command line tool to work with netmasks / CIDR notation [closed]

I'm terrible at working out network subnets in my head. Is there some command line tool for linux (ubuntu packages a plus), that lets me put in 255.255.255.224 and it'll tell me that is a /27?
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0answers
47 views

Cannot Reach Secondary Subnet on Same Interface

I am running a Cisco 1841 which has an unmanaged Dell 2848 connected to it. Connected to a WIC card in the 1841 is a fiber run which goes to a subnet of devices. The primary subnet is 192.168.2.0/24, ...
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2answers
75 views

Am I meant to allocate a /64 to every host?

I have been reading conflicting sources and seeing different behaviours about how a CPE router should be assigning IPv6 addresses. RFC3633 seems to imply that each host should get /64, while RFC6204 ...
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2answers
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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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1answer
25 views

Juniper SSG20 Additional subnet on adsl interface

I've configured a Juniper SSG20 to have some clients natted to the internet with the main ip address (X.X.27.90/30) of my IPoA ADSL connection but i have also some servers i wish to connect with a ...
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7answers
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Advice for configuring a SonicWALL NSA 2400 to use two subnets and L2 Bridge Mode

This post is not an exact duplicate of How to configure remote access to multiple subnets behind a SonicWALL NSA 2400 . However, I am having this problem, almost verbatim. Unfortunately, we even have ...
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3answers
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Force Windows Local Subnet Traffic through a Gateway

We are attempting to route all traffic from a certain machine to a gateway. This works ok for traffic destined for subnets outside of the machine's subnet. However, traffic to machines in the same ...
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2answers
733 views

XenServer 6.2 - Hetzner host - Additional Subnet Configuration

I have a dedicated server on Hetzner, on which I have installed XenServer 6.2 . The server comes with one public IP address. I purchased an additional subnet containing 6 usable IP addresses, for use ...
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38 views

Pass multicast packets between subnets. Which static routes need to be added?

I have searched forever but cannot find a clear instruction how to set this up. I have a router providing two LANs over bridges LAN 1 on 192.168.1.0/24, bridging two access points (2.5 and 5GHz) ...
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0answers
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How can you calculate IP address subnet ranges? [duplicate]

If you're given: Number of needed subnets: 2 Network Address: 195.223.50.0 I can answer the following: Address Class: C Default Subnet Mask: 255.255.255.0 Custom Subnet Mask: 255.255.255.192 ...
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66 views

Make local subnet clients get redirected like public clients, when requesting a redirected outside port on the firewall

I have a server that also functions as a firewall for the 192.168.1.0/24 subnet via iptables. It also double as a VM Server. Both the VM's and the local machines share the subnet. The servers ...
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1answer
44 views

How to use multiple IPs on dedicated server?

I have this dedicated server with /29 IPv4, and I would like to know how to use all the IPs I have avaliable. How to choose? How can I know which are the IPs? Can I use them like proxies with proxycap ...
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What's the difference between .0/32 and .1/24 in CIDR? [closed]

We're specifying CIDR addresses in AWS rules, and I came across something I don't understand. /32 means one single address. So 10.0.0.0/32 means only the single address 10.0.0.0. But an address ...
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0answers
15 views

IP Address Subnetting [duplicate]

For my computer networks class, I'm having a hard time understanding how to subnet IP into different networks. Here is a textbook question that I'm having difficulty on: Suppose an organization was ...
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0answers
45 views

Ubuntu Router to connect two networks via IPv6

I am currently in the situation that I want to add one network of homogenous linux nodes to an already existing windows network. For administrative reasons the linux nodes are not going to be added to ...
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1answer
159 views

connect to db instance in private VPC subnet with MySQL Workbench

How do I connect to an AWS (or other) instance in a private subnet in a VPC using MySQL Workbench ? My arrangement is a typical aws Scenario 2 : I can: - SSH into my NAT instance located in my VPC ...
273
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6answers
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How does IPv4 Subnetting Work?

This is a Canonical Question about IPv4 Subnets. Related: How does IPv6 subnetting work and how does it differ from IPv4 subnetting? How does Subnetting Work, and How do you do it ...
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267 views

can't connect aws VPC private instance to internet through NAT

trying to install a LAMP stack on an aws instance in a VPC private subnet using Scenario 2 described here: http://docs.aws.amazon.com/AmazonVPC/latest/UserGuide/VPC_Scenario2.html I've set everything ...
4
votes
3answers
188 views

Windows DNS: Is there a way to partition a domain based on subnets

In our organization, we have two separate groups which share network address space and a domain. A couple of slices of /24 are allocated to my group, while the rest is allocated to our internal IT ...
3
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4answers
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Are network and broadcast IPs supposed to respond?

I have a /24 network that is subnetted into a bunch of small chunks. I have recently gone into each router on the network (mostly Cisco) in order to document how this network had been divided. Now ...
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4answers
8k views

Finding the first and last address of a block of IP addresses with subnet mask

I am not sure if this is the right place to make this question but I thought this is one of the most appropriate SE's site to make a question on networking. Please move it to other more appropriate ...
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1answer
62 views

Why do some network services require that the client and server be on the same subnet?

Periodically I run into client-server communication issues over a network, where the client cannot see the server, whereas other services don't have an issue. Many times, if I have to phone up support ...
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32 views

Windows Server spamming devices on other subnets on port 445

I have a Windows Server 2012 that every few seconds sends packets destined for port 445 on local IPs on other subnets. The IPs on other subnets it is trying to reach are devices such as VoIP phones, ...
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44 views

Route part of a subnet to a different gateway

Data network is 10.220.0.0/20 DG is 10.220.1.19 I am trying to have all traffic in 10.220.8.0 - 10.220.15.255 (10.220.8.0/21) routed to this gateway: 10.220.1.251 I can't seem to accomplish this at ...