Questions tagged [subnet]
A subnetwork, or subnet, is a logically visible subdivision of an IP network.
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What is the difference between a VLAN and a subnet? [closed]
I have read numerous forums and articles regarding VLANs and subnets.
However, I haven't understood the functions of each apart from the following:
Subnets allow the segmentation of a network
VLANs ...
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Why are subnet-masks relevant for the individual computer on the network?
I understand how subnet-masks are used to divide a network into sub-networks, but, why does every computer in the network need to know the subnet-mask and not just the router?
I could understand it, ...
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What does it mean to have a subnet mask /32?
I see in this question, the routing table has:
192.168.1.1/32 link#4 UCS 2 0 en0
openwrt.lan 46:94:fc:63:fc:7 UHLWIir 11 3610 en0 1200
...
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Why do we need subnet mask?
Since a IPv4 address already gives the information of the network and and host, why do we still need a subnet mask?
The 1st Octet already specify the network class (1-127: A, 128-191: B, 192-223: C ...
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What is a subnet mask, and the difference between a subnet mask of 255.255.255.0 and 255.0.0.0?
My DSL/WiFi router provided by my ISP has an internal IP address of 10.0.0.138, the addresses provided by DHCP are in the format of 10.0.0.xxx.
Now, I want to start using static IP addresses on my ...
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Why isn't 255.255.249.0 a valid subnet mask?
I was just wondering about this question above and I would greatly appreciate it if someone can explain why 255.255.249.0 isn't a valid subnet mask.
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Are subnets always contiguous 1s? [duplicate]
I understand the basic premise behind subnet masks, such as 255.255.255.0. But all the subnet examples I’ve seen have been (from left-to-right) contiguous 1s (HI bits). For instance, 255.255.0.0 (/16) ...
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What is the difference between a subnet mask and a netmask?
Is there any logic in using two different names for determining host ID and net ID?
For example, if you type print route in a Command Prompt you get things with netmask, but the IPv4 settings seems ...
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Why is my subnet mask 255.255.255.255?
I have a modem which used for internet broadband and I got an IP address in the 'A' class 10.x.x.x and have netmask 255.255.255.255.
What does 255.255.255.255 mean exactly?
When I try to sniff with ...
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Communicating with devices on a different subnet
Let me start this off by saying that I am very new to how IP Address / Subnet Addresses work, and networking in general. This stuff is generally mystifying, and I've had a hard time understanding ...
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Is there any reason to subnet a home network?
For networks I understand we set a netmask on each computer to let it know what IPs it can talk to without going through the router - IPs on the same subnet can talk directly to each other and do not ...
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What does (Preferred), (Tentative) and (Duplicate) mean against an IPv4 Address with ipconfig
I have been tinkering with subnets and have noticed the above as annotations to the IPv4 line of ipconfig.
IPv4 Address. . . . . . . . . . . : 192.168.1.241(Tentative)
IPv4 Address. . . . . . . . . . ...
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How to create a separate subnet for wireless access?
I need to configure my wireless router so all wireless devices are on a different subnet (192.168.2.1).
The wireless devices should be able to access the internet, but ideally not the workstations on ...
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What are the essentials of a Subnet mask?
What is the use of a subnet mask?
What is the below output conveying to the user?
Connection-specific DNS Suffix . :
IP Address. . . . . . . . . . . . : 192.168.1.2
Subnet Mask . . . . . . . . . ...
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How to put two subnets next to each other?
I've been using this calculator http://www.subnet-calculator.com/cidr.php, and I'm trying to figure out how to put two different subnets next to each other.
For example, I want to have a /27 subnet ...
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Where are addresses from the network 0.0.0.0/8 used in practice?
I read that this pool:
Means "these hosts" in "this network"
Is used for self-identification
Is used for broadcast messages
My questions are:
Where exactly these addresses can be found?
Which ...
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Why can't my OpenVPN client access machines on same LAN as OpenVPN server?
I have configured OpenVPN on my Linux server and Windows client according to the instructions here. My client can access the server, but can't get any further onto the LAN.
My Server is 10.23.29.64/...
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Why is ip address listed as 172.18.0.150/24?
Why is IP Address listed with this notation 172.18.0.150/24? I mean the ip is 172.18.0.150 only why it haves /24?, and then whatever what subnet that is on should be someone else's worries, no?
3: ...
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Why is it improper network design to have two physical NICs, one machine, same subnet, same netmask, same gateway, two different IP addresses?
All I read and can see says to put two different IP addresses on one NIC. I thought if I had two NICs, I'd be better off for speed/throughput.
Why is it a wrong topology to have two separate ...
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Trying to understand the interactions between two different subnets on the same network
I have a 10.0.0.0/8 network split into two parts. A DHCP server hands out addresses 10.0.0.10 to 10.0.0.150 with a class A mask (255.0.0.0). This is my “Guest” portion of the network.
Authorized ...
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192.168.x.x addresses with subnet 255.255.0.0
We are designing a network where we have
192.168.100.52
192.168.110.13
Initially the subnet mask was 255.255.255.0, so clearly these first two machines will not communicate with each other without ...
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My IP addresses changed from 192.168.2.xxx to 192.168.1.xxx. I can't reach the switch anymore
My connection is now on fiber and since that was realized, all my IP addresses shifted from 192.168.1.xxx to 192.168.2.xxx.
I have tried to revert them back to 192.168.1.xxx, but without luck. Now for ...
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Can you have a class C IP address with a subnet mask of 255.255.0.0?
Can you have a class C IP address with a subnet mask of 255.255.0.0?
What happens when you have a setting like this?
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"Destination port unreachable" when pinging computer in another subnet
In my home network, I connect to the Internet through a router (192.168.1.1). I also have another router (192.168.1.15, 192.168.2.1), this one using OpenWRT, configured as a wireless client. One of my ...
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Non-contiguous Subnet Mask
In this question:
Is 225.225.225.128 a valid subnet mask?
The accepted answer states that the subnet mask must be contiguous. A few comments reference RFCs stating that this is the case. However, I'm ...
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Set up two (2) IP addresses on the same network card?
I think it is possible to set up 2 IP addresses and subnet masks on one NIC in Windows XP.
How can this be done?
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Traceroute hops in the same subnet
in what case is there two neighbor hops in the same subnet in a traceroute output? As I know it should be only source addresses and each router interface should be in different subnet?
E.g.:
1 ...
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How do I join two subnets with two DD-WRT routers?
I have two separate DD-WRT routers which I would like to bridge together so that computers connected to each are on the same subnet (so that multicast can work between them for UPNP/DNLA media sharing)...
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Why subnet mask for IP 10.0.1.4 is 255.255.255.0?
Well I'm not sure whether I'm missing something here. But all I've read is that if first octet of IP is within 0 - 127 then it is categorized as Class A subnet and correspondingly Subnet Mask for ...
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How to correctly set the subnet mask installing Linux Ubuntu 20.04 server? ERROR: '172.16.182.216' is not contained in '255.255.255.0/24'
I am not a system engineer or a network expert (I am more a software developer)
I am trying to install an Ubuntu Server using static IP address. I am using the information provided by a collegue.
...
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Is 225.225.225.128 a valid subnet mask?
I have been told that we have two devices on a network:
10.40.225.142 and 10.40.225.144
These devices both have
Gateway 10.40.225.129
Subnet mask 225.225.225.128 (note 225 is Not a typo)
These ...
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How to find CIDR subnet for a public Internet IP address?
Usually I do not worry about subnet of an IP address on the public Internet, but after I began using Amazon EC2 firewall, it got me thinking.
EC2 firewall configuration requires an IP to be written ...
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How do you route within an Amazon VPC subnet?
I have an Amazon Virtual Private Cloud that looks like this:
10.40.1.1 Internet Gateway
10.40.1.5 My OpenVPN Instance
10.40.1.100 My Windows Box
What I want is traffic from the Windows box ...
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OpenVPN: Route only specific subnetwork through vpn - works for single IP adresses
I was trying to route only specific subnet/single through open vpn.
I have read several questions like this on superuser, and even found
good answer to my question.
So I am now able to route single ...
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How do I know if two machines are on same LAN?
I am very poor with Computer Networks, even though I took class in my grad school.
I keep forgetting about subnets and masks and what not!
Currently, I am playing with Docker and Erlang and was ...
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how to split up network into two subnets with only one router
I have one router on my home network. This acts as the main WiFi access point for all devices, as well as being connected to a simple switch for my home lab. I would like to be able to isolate my home ...
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Home network with two routers and just one Wifi
I know it is a pretty lame question, but I am not a pro in networking, so I will still ask it. And I will try to explain details where possible.
I want to create the following setup:
Phone line is ...
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Why does it seem like I am losing IP addresses after subnetting with the subnet mask of 255.255.255.192/26?
Note: I'm not referring to 2 IP addresses that gets lost when using subnetting.
I think my math is wrong somewhere. Here is what I'm doing.
Class B Private IP Range: 172.16.0.0 to 172.31.255.255
To ...
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What is the diference between IP subnet mask 255.255.254 .0 ... or 255.255.255.0? [closed]
What is the diference between IP subnet mask 255.255.254.0 and 255.255.255.0?
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Windows XP doesn't like small subnets?
This totally sounds like a bug to me, because my subnet mask and IP address should be valid by all accounts.
My ISP has assigned me a fixed IP address of 65.110.7.20, with a subnet mask of 255.255....
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Can a subnet have more than one gateway?
I am new to networking.
While reading Network+ Guide Networks books, I came to Subnets but the book does not mention how many gateways a subnet can have. For example for 192.168.1.0/24 the gateway is ...
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I'm using Cisco Packet Tracer for Simulation and got error "ip address overlaps with..etc"
The 1st row is for my router and the 2nd row is for my LAN. What's wrong? Is my IP addressing and subnetting wrong? I already checked my configuration.
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How can I find any domain name that resolves to IP within a given net range?
For example, given the range:
172.128.0.0 - 172.191.255.255
I need to find some domain that resolves to an IP-adress within the range. Is it possible ? I'm using a Linux system.
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Lan to Wan setup how to connect two subnets
I hope someone can help me with issues I have with my home network. I have a Billion 7700N modem/router and currently I added a Western Digital N600 dual band router. By default (following setup DVD ...
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What is the effect or purpose of subnet on client PCs?
I understand that the subnet mask when combined with an IP is used to define the range of IPs that the router is responsible for routing. e.g. a router with 192.168.3.1 subnet 255.255.254.0, will ...
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How to give device on modem’s subnet a second IP on the routers subnet?
I’m new to network stuff so please excuse me if I miss something obvious
I have a modem with the subnet/DCHP 192.168.1.x and a device on it with the local IP 192.168.1.66. This device acts as a server ...
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Create private network from public wifi
My question is similar to this one, which was never answered. I live in an old apartment building that is not wired for internet access, and therefore pay a monthly fee to access an XFINITY® WiFi by ...
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iptables on openwrt router: logging connections to a host from clients on the same subnet
I am trying to setup an auto wake-on-lan setup using my router that is running OpenWRT 14.07, Barrier Breaker.
My idea is that the router monitors any connection attempts to the host I want to wake up ...
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Broadcast address in IPV4
I have a small network with the subnet mask 255.255.255.240 and the IP range is 192.168.2.1 - 192.168.2.12. From 192.168.2.1, I want to broadcast a packet. I don't want this packet to go anywhere ...
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How to calculate CIDR notation from entries in a routing table
I have some entries in a routing table that were created using longest prefix matching, and I have to use those entries to determine the a.b.c.d/x notation (CIDR).
This is an example entry:
11001000 ...
