Questions tagged [ip]
IP - Internet Protocol, the most commonly-used set of rules for dispatching data across a large computer network.
2,850
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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.
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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 <toolname> w.x.y.z => mycomputername
I've tried:
nslookup: seems to be forward look-...
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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 ...
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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 ...
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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.
$ ...
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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 ...
user62491
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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 ...
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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 ...
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votes
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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 ...
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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 ...
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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...
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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 ...
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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 ...
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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 ...
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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
...
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Why can't I reach my Amazon EC2 instance via its Elastic IP address?
The server works fine via the Amazon assigned DNS entry, but I cannot reach it (using a browser) via the Elastic IP address Amazon assigned the box. Ping does not work either. I am trying to confirm ...
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How to get a list of all IP addresses (and ideally device names) on a LAN?
Our network gave an error that there was an IP address conflict and I'd like to find what all the device IP addresses are. (I've also had need of that before). (update/clarification:I'm looking for a ...
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Can a single network card have 2 IP addresses?
Are network cards and IP addresses a one-one map?
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Force local IP traffic to an external interface
I have a machine with several interfaces that I can configure as I want, for instance:
eth1: 192.168.1.1
eth2: 192.168.2.2
I would like to forward all the traffic sent to one of these local ...
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Why do we ping the IP 4.2.2.2 to test connectivity?
For as long as I can remember, I've always used the IP 4.2.2.2 when testing network connectivity using ping. What is significant about this IP, and when did this practice start?
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Why does typing an IP address instead of the corresponding domain name not show the website? [closed]
> host example.com
example.com has address 93.184.216.34
example.com has IPv6 address 2606:2800:220:1:248:1893:25c8:1946
I type 93.184.216.34 instead of http://example.com in Chrome. It doesn't ...
user201874
39
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4
answers
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How do I find out what my IP Address of my MySQL host is?
I have a free domain running at x10hosting (x10.bz), and I want to find out the IP Address of my MySQL host for it, so I can contact the MySQL database from another host. I've already added that host ...
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Nginx - How to redirect users with certain IP to special page
I run quite a big image gallery and there are 5 visitors that create an enormous amount of traffic by downloading the whole site every day using webcopiers. Those visitors have static IPs as it seems. ...
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How to route different traffic thru different network interfaces (in Windows)
I've searched for details on how to do this but I've been unsuccessful - I wondered if someone could offer up some advice.
So, let's say I have 2 network cards (LAN and 3G in my instance), both ...
user28599
38
votes
5
answers
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Users with Google's IP address. How is it possible?
I have a spanish website and I do not allow people from non-european countries to register and to login.
Some time ago I started to receive messages from users who can not login. When I ask for their ...
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How to see incoming IPs in Linux?
I am wondering what is the command/utility to have a real-time view of incoming IPs to my server, ideally along with the port and connected.
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Is it valid to have part of an IPv4 address set to zero?
I am working on a change in a Java EE application that would authenticate based on the user's IP address using ServletRequest.getRemoteAddr. We store IP address ranges (FROM_IP and TO_IP) in a ...
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Is 0.1.2.3 a valid IP address?
Are IP addresses with all zeroes in the first octet valid?
For example, can 0.1.2.0/24 be a valid subnet, with network address 0.1.2.0, broadcast address 0.1.2.255 and an usable address range from 0....
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Is it possible for two hostnames share the same IP address?
Can anyone explain whether it is possible for two hostnames to share the same IP address?
And what about if one hostname represents more than one IP address, is that possible too? Why?
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Why "Nexthop has invalid gateway" when it seems to be defined?
I have my own wireless router to which a remote VPN client, 10.7.0.6, is connected. I want traffic from one of the wireless clients to go through it, but I'm getting "Nexthop has invalid gateway". (I'...
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Where does Amazon publish the range of IP addresses used for EC2 instances by region?
How can I keep updated of changes to the range of IP addresses that Amazon will use for EC2 instances. I want to add a range of IPs to my firewall settings to allow access to my 'ground based' mysql ...
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Remove IP with ip command in linux
If I add two IPs like this:
ip addr add 1.1.1.1/24 dev eth2
ip addr add 1.1.1.2/24 dev eth2
and then I try to delete one of like this:
ip addr del 1.1.1.2/24 dev eth2
BOTH IPs will be deleted and ...
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What is the network address (x.x.x.0) used for? [duplicate]
It appears to be common practice to not use the first address in a subnet, that is the IP 192.168.0.0/24, or a more exotic example would be 172.20.20.64/29.
The ipcalc tool I frequently use follows ...
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How many computers can have the same public IP?
I've got a list of hundreds of page requests from the same IP and I need to know if these could be requests by different computers.
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Can the IP address for an HTTP request be spoofed?
On a website I am building, I plan to log the IP addresses of submissions, just in case it's necessary. I don't mind proxies, but outright spoofing your IP address would defeat the purpose.
To ...
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Why does this URL with excessive preceding dots resolve to an IP address?
http://.................1168951531
Which, when put into chrome, previews to the URL http://69.172.200.235/, which redirects (by external server response code 3XX) to www.test.com, but that is outside ...
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What are the differences between Floating IPs and Virtual IPs?
This might be a pedestrian question but what is the difference between a "Floating IP" address and a "Virtual IP" address? Are they synonyms?
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How can I display the IP address of an interface?
If I want to display the IP address that is assigned to eth1, how can I do this in Bash?
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Under what circumstances is TCP-over-TCP performing significantly worse than TCP alone (2014)?
Many admins keep perpetuating - on ServerFault and elsewhere - how bad of an idea TCP-over-TCP is, e.g. in VPNs. That even the slightest packet loss will make one suffer from at least severe ...
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Any way to find unused IP addresses on my network?
How can I locate unused IP addresses on my network? The DHCP server keeps assigning the same address and I need a different IP address to test my application with. The software would need to run on ...
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How do I use Linux to find unused IP addresses on my network?
I've got access to two computers (A and B) on a network. Both have got a static IP address with a subnet mask of 255.255.255.128 (I checked that a DHCP server was not being used). I want to configure ...
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Static IP vs DHCP Reservation
When setting up a network in need of static IP addresses I've come across at least two ways of doing so.
A: Router/Gateway
In particular, on my Buffalo router, under DHCP Server, there is the option ...
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How to check IPv6 address via command line?
How do I check the IPv6 address via command line?
For IPv4 I simply use:
curl ipinfo.io/ip
This doesn't work for IPv6.
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How can I send visitors to the closest server using DNS?
Is there a way to localize dns entries? Meaning, that users from asia resolve mydomain.com to another ip than users from usa or europe.
This would be helpful to give the users the server nearby. DNS ...
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Is there an "official" name to the 0.0.0.0 IP address?
As 127.0.0.1 is known as the loopback address, is there a shorter term to refer to 0.0.0.0 other than "the IP address who means all IP address on local machine"?
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What is the difference between 0.0.0.0/0 and 0.0.0.0/1?
In the history, I mostly used 0.0.0.0/0 for "match every IP address". Recently, I saw a 0.0.0.0/1 subnet filter.
What is the difference between 0.0.0.0/0 and 0.0.0.0/1 and what's the ...
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How can I get the IP address of a remote desktop client? And how can I trigger a shell command upon RDP connect?
Is there a way to determine the IP address of a remote desktop client using PowerShell (or some other method) on the server? (Windows Server 2008 R2 x64 is what I'm using)
EDIT: I find that I can ...
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IPv4 CIDR Ranges for Everything except RFC1918
I'm looking for a list of CIDR blocks for "The Internet", i.e. everything from 0.0.0.0 to 223.255.255.255, excluding RFC1918 address space of 10.0.0.0/8, 172.16.0.0/12, and 192.168.0.0/16 (yes, I know ...
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ip address scope parameter
In Linux, the command
ip address add [...]
has a scope argument. The man page says that the scope is "the scope of the area where this address is valid". Follows the list of legal scopes:
global
...
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