Questions tagged [ip-address]

IP address is a numerical label assigned to each device participating in a computer network that uses IP for communication.

An Internet Protocol address (IP address) is a numerical label assigned to each device (e.g., computer, printer) participating in a computer network that uses the Internet Protocol for communication. An IP address serves two principal functions: host or network interface identification and location addressing. Its role has been characterized as follows: "A name indicates what we seek. An address indicates where it is. A route indicates how to get there."

The designers of the Internet Protocol defined an IP address as a 32-bit number1 and this system, known as Internet Protocol Version 4 (IPv4), is still in use today. However, due to the enormous growth of the Internet and the predicted depletion of available addresses, a new addressing system (IPv6), using 128 bits for the address, was developed in 1995,[3] standardized as RFC 2460 in 1998,[4] and its deployment has been ongoing since the mid-2000s.

IP addresses are binary numbers, but they are usually stored in text files and displayed in human-readable notations, such as 172.16.254.1 (for IPv4), and 2001:db8:0:1234:0:567:8:1 (for IPv6).

The Internet Assigned Numbers Authority (IANA) manages the IP address space allocations globally and delegates five regional Internet registries (RIRs) to allocate IP address blocks to local Internet registries (Internet service providers) and other entities.

Source: Wikipedia.

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Get the interface and ip address used to connect to a specific host (ip)

I'm sure this has been asked and answered before, but I wasn't able to find it, so hopefully this will at least link someone to the right place. I want to find out my local interface and ip address used to reach a certain host. For instance, if I…
umop
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How reliable are IP address-based firewall restrictions?

On some of my production systems that need to be accessible outside of the LAN I will sometimes add a firewall restriction at the edge to only permit traffic on, say, RDP from a specific origin IP address or block. Of course, the IP needs to be…
tacos_tacos_tacos
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How even is the distribution of digits in the last part of an IPv4 address?

I have a redirect script operating on a website I created. It sends 1/3 of visitors to site A, 1/3 of visitors to site B and 1/3 to site C. It works by dividing the last part of the users IPv4 address (0-255) by 3, and they are redirected to site A,…
Adjam
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Should I split my data network into 2 separate VLANs?

I am currently using 10.54.0.0 /19 for all my desktop clients and printers. We have approx 550 clients/printers. Besides bandwidth, which is barely being utilized, are there any other reason to split up my data network or go to a smaller subnet…
Ruisu
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How do I get a distinctive IP Address?

I see Google has 8.8.8.8 and CloudFlare has 1.1.1.1. How do I get myself a distinctive IP address? What's involved in acquiring something that has a pattern in it?
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What is this "Thing" on my network?

I was using AMD's magic packet utility to build a list of computers to do wake-on-lan and it found these entries: 224.0.0.22 igmp.mcast.net 01-00-5e-00-00-16 224.0.0.252 *NameNotFound* 01-00-5e-00-00-fc 239.255.255.250 *NameNotFound* …
Peter Turner
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How can I find out who is hosting a certain domain?

I've got a friend who has been completely abandoned by his previous website guy. Yes, the guy was cut rate, and yes, you get what you pay for. Anyway, he has asked me to help him untangle all that has been done. Starting now, he wants to know who…
Matt Dawdy
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Best choice of private addresses for a "device area network"

I'm building an appliance consisting of several subdevices connected by ethernet inside the appliance. The appliance will connect to the customer network. The customer network can be using private IP addresses. An address conflict with the…
proski
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DMZ subnet: to NAT or not to NAT?

I'm looking at setting up a DMZ behind a Cisco ASA that will contain a large number of HTTP front-end load balancers and SSL offload services - over 100 IPs, concentrated on a smaller number of hosts. In the past I've kept all the hosts on RFC1918…
natacado
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How do I configure Shrewsoft's VPN client to only route traffic to a certain IP address through the VPN?

We're using Shrewsoft's VPN client to connect to a third party development server. However, it seems to be configured to send all or nothing through the VPN. The devs have to disconnect from the VPN to get email/internet access back. The server that…
dommer
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How do I create a virtual IP address?

i am a student so i am pretty new at this but i am making a web cluster with two web servers so that if one server fails the website still stays up. my question is how do i assign a virtual IP address to both machines so that I have one IP address…
slufb63
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ntpd gets "connect: invalid argument" on 0.0.0.2

It appears the reply for pool.ntp.org changed recently. This is making my CentosOS 6 ntp servers unhappy. $ host pool.ntp.org pool.ntp.org has address 0.0.0.2 pool.ntp.org has address 83.209.8.142 pool.ntp.org has address…
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Where can I find a list of IP addresses of hosting providers?

I am attempting to fend off a spam attack against a web api I run and would like to obtain a list of IP addresses of public web hosting providers from which spammers are launching their attacks. I'm talking about sites like bluehost, rackspace,…
esilver
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Amazon EC2 multiple private IP addresses per instance

I have a scenario where an application requires multiple private IP addresses but does not require the resources of multiple instances. In this case, I would like to run multiple jboss instances on the same EC2 instance without port mangling. I've…
dhartford
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How to bind a non-local IPv6 address?

Is there an equivalent of net.ipv4.ip_nonlocal_bind for ipv6 ? Need to start my nginx on boot on such an IP... My Ubuntu doesn't have this IPv6 assigned on eth0 quickly enough despite this /etc/network/interface : iface eth0 inet6 static address…
Valentin
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