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Questions tagged [ip]

IP - Internet Protocol, the most commonly-used set of rules for dispatching data across a large computer network.

IP (Internet Protocol) is a protocol which encapsulates data for transit across the Internet and encodes its source and destination addresses, among other parameters. It implements the network layer (layer 3) of the OSI model.

Questions related to IP (addressing, routing, and protocol issues) fall under this tag; questions merely containing an IP address do not.

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How to bind MySQL server to more than one IP address?

Is there a secret way to bind MySQL to more than one IP address? As far as I can see the bind-address parameter in the my.cnf does not support more than one IP and you can't have it more than once.
BlaM
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What's the command-line utility in Windows to do a reverse DNS look-up?

Is there a built-in command line tool that will do reverse DNS look-ups in Windows? I.e., something like w.x.y.z => mycomputername I've tried: nslookup: seems to be forward look-up only. host: doesn't exist dig: also doesn't exist. I…
alastairs
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What's the difference between IP address 0.0.0.0 and 127.0.0.1?

I know that 127.0.0.1 ~ 127.255.255.254 are the loopback IP addresses for most modern operating systems, and these IP addresses can be used to refer to our own computer. But what's 0.0.0.0? It seems it also refers to the local computer, so what's…
Jichao
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What is the difference between Unix sockets and TCP/IP sockets?

It's from this answer: https://stackoverflow.com/questions/2482411/is-this-pdo-bug-fixed-now/2482424#2482424 When the host is "localhost", MySQL Unix clients use a Unix socket, AKA Unix Domain Socket, rather than a TCP/IP socket for the connection,…
apache
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What is the difference between unicast, anycast, broadcast and multicast traffic?

I have never had the privilege of working in an environment that required complicated routing or if it did require it, it was handled upstream of me. I've always used very simple static routing configurations and never needed to do any multipath…
user62491
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What is this IP address: 169.254.169.254?

I have always noticed an IP something "169.254.x.x" in my routing table even when I am not connected to any network in my Windows operating system. In Linux, when I list my routing table. $ ip route show I get an entry like 169.254.0.0/16 dev eth0…
pradeepchhetri
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How to determine the hostname from an IP address in a Windows network?

My LAN has 50 Windows hosts. At the Windows command line I try ping to get the IP address of a running Windows machine. The question is how to get hostname of a specific IP address in the same Windows workgroup? Another question is how to know the…
billyduc
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What is "anycast" and how is it helpful?

I'd never heard of anycast until a few seconds ago when I read "What are some cool or useful server/networking tricks?". The wikipedia "Anycast" article on it is quite formal and doesn't really evoke a mental picture of how it would be used. Can…
username
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How to scan local network for SSH-able computers?

I am often on one computer in my house and I would like to SSH to another one, but often don't know the IP address of the one I want to connect to. Is there a way, from the command line, to scan the local network so I can find the computer I want to…
Andrew
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Block range of IP Addresses

I am getting bombarded with attempted hacks from China all with similar IPs. How would I block the IP range with something like 116.10.191.* etc. I am running Ubuntu Server 13.10. The current line I am using is: sudo /sbin/iptables -A INPUT -s…
Stephen Cioffi
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What does [::] mean as an ip address? Bracket colon colon bracket

When I run netstat there are some entries such as TCP [::]:8010 computername LISTENING What does that mean? It is impossible to search for...
carpat
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Why would you use IPv6 internally?

Of course, I realize the need to go to IPv6 out on the open Internet since we are running out of addresses, but I really don't understand why there is any need to use it on an internal network. I have done zero with IPv6, so I also wonder: Won't…
KCotreau
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associate name with ip for ssh?

Let's say I just have an ip address for a server and I don't have a domain with it (it's just a database server, so it doesn't need a domain). I don't want to have to remember the ip address every time, so is there a way I could still use the syntax…
Matthew
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Debugger for Iptables

I'm looking for an easy way to follow a packet through the iptables rules. This is not so much about logging, because I don't want to log all traffic (and I only want to have LOG targets for very few rules). Something like Wireshark for Iptables. Or…
Chris Lercher
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Why is tampering with the TTL of IP dangerous?

I've been reading the iptables man-page (light bedtime reading) and i came across the 'TTL' target, but it warns: Setting or incrementing the TTL field can potentially be very dangerous and Don't ever set or increment the value on packets that…
Robbie Mckennie
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