How To Resolve Ip Addresses To Domain Names
I know it is possible to resolve IP addresses to host names but can IPs be resolved to domain names?
Yes, you can resolve an IP Address back to a hostname.
Within DNS, an IP Address can be stored against a PTR record. You can use nslookup to resolve both hostnames and IP addresses, though use of nslookup has been deprecated for quite some time.
For best results, you should really get a hold of the dig tool. If you’re a linux user, this is available as part of dnsutils , or similar package. If you’re a windows user, you can follow instructions such as these to install dig.
You can then do:
To lookup the IPv4 address for a host, or:
dig AAAA < hostname>
To lookup the IPv6 address for a host, or:
dig PTR ZZZ.YYY.XXX.WWW.in-addr.arpa.
To lookup the hostname for IPv4 address WWW.XXX.YYY.ZZZ , or:
dig PTR b.a.9.8.7.6.5.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.
You can use nslookup, dig, or other network tool to possibly get a domain name for an IP address, but it’s not necessarily going to be the one you’re expecting.
Unlike normal DNS lookups, where many names can resolve to a single IP address, reverse DNS lookups can only resolve to a single name, and that’s handled by whomever controls the reverse DNS information for the IP block in question. Nobody else can set up a PTR record on a random IP address block. This is in contrast to “normal” DNS lookups, where anyone can set up a domain name and create A records pointing at whatever IP addresses they’d like.
How To Get The Ip Address Of Your Domain
There are a few ways to find the IP address that has been assigned to your domain. This article will cover 4 methods that you can use to find this information quickly.
To utilize the steps outlined in this article, you’ll need to ensure that your computer has access to the internet and that you know the name of the domain that you’d like to lookup.
Get The Domain Name From Ip Address
I am using the following commands to get the domain name using the IP address
dig -x IPaddress
But it gives me some host names like ns1 etc. Is there any bash command that can give the actual domain name?
- May 18, 2018 at 15:14
- And what you expected.
Using the +short option of dig you can get only the dns name.
dig -x 8.8.8.8 +short | awk -F '.' ''
There’s probably a nicer way to reassemble it with awk Or just return the DNS Domain.
Have a read through the QUERY OPTIONS in man dig
When I do it I get something like this
dig +short -x $
I get
host-198-51-100-0.as13285.net.
This is not the original domain name, because the domain name system has no easy way to look it up, as the real name is not registered in the database, however the one that was returned was. It would be to expensive to ask every DNS server in the world.
In addition there is a many to one relationship. Each IP can have many domain names .
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Host Name Or Domain Name
There is often confusion about what is a host name and what is a domain name.
A domain name is the name that is purchased from a registrar. It will be something like hcidata.com or hcidata.co.uk. Note that there is no www at the beginning of a domain name. A domain name can be subdivided into sub-domains – for example www.hcidata.com. Once you own a domain, there is no reasonable limit to the number of the sub-domains you can create. A sub-domain can be allocated to a host machine – for example a PC. In fact many sub-domains can be allocated to the same host machine. The way sub-domains are allocated to a host machine is to create a record in the DNS that records the sub-domain name and the IP address of the host machine. Any requests for a sub-domain are converted to an IP address by DNS and the IP address is used to route the request through the network until it reaches the host machine.
In the early years of the Internet, each sub-domain would have a unique IP address so it was common for a host machine to have only one sub domain name. Nowadays, the common practice is to have many sub-domains with the same IP address. It is also common for the domain name to be converted to the IP address of the host machine that runs the www sub domain.
How To Get Hostname/domain Name From Ip Address In Linux
Often new system administrators need to find a hostname or domain from a given IP address in Linux. It might seem like a difficult task but it quite easy. This process is called reverse DNS lookup. Generally, operating systems and browsers lookup IP address of a given domain name. This is called DNS lookup. In this article, we will cover how to do reverse DNS lookup. In other words, we will learn how to get hostname/domain name from IP address in Linux.
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Domain Name Server Zones
The internet traffic and the number of websites have grown phenomenally in the last decade and managing the traffic is not easy. At any point in time, millions of users are accessing internet sites whether its to watch movies, play games, chat with friends, read news and blogs theres constant traffic. Directing visitors to the websites that want to view needs proper controls and this is what the domain name server zones provide.
For example, domains with .com and .info and .net cannot be placed on the same set of servers. It would slow down the queries, therefore to avoid congestion they are placed on different servers. These zone servers are replicated at various locations. In simple terms the .com servers would only provide IP address of domains that have .com in them and another set would be providing information for domains having .net in them.
Without zones, it would be a virtual nightmare to manage the internet. All domain name servers have backup servers at physically different locations.
What Is Ip Address
An IP address refers to the Internet Protocol address. An Internet Protocol address is your hardware address on the network. E.g., Every computer system has an IP address when it is on a network. An IP address is always unique for all devices connected within a network.
The IP address can be different for the same computer device every time when it gets connected with a network. However, the IP address of a website is always the same that can be used to access a website on the web.
You can access a website either using its web address or IP address. Basically, it is difficult to remember the number of IP addresses compared to website names.
Drawback
We all know that IP address is difficult to remember while hostname is easy to call and remind. Thereby hostname came into existence.
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How To Get Domain Name Only From An Ip Address For Whois Lookup
I’m trying to run a who-is command on an arbitrary IP address for my internal use as such:
function echo_whois
The issue is that I can’t seem to find a way to get a domain name from the host name.
Here’s an example, say for IP 114.237.31.186 that resolves to 186.31.237.114.broad.lyg.js.dynamic.163data.com.cn.
Is there a function in PHP that can do that?
- Is the DNS-Entry possibly kind of new? If so, the reverse-entry might be cached on some resolvers. For instance when I run dig in trace mode like this it works just fine: dig -x 114.237.31.186 +trace ) on my machine returns the DNS entry as expected) ArSeNMar 7, 2020 at 20:56
- You need reverse IP lookup, but don’t forget that an unique IP may be pointed by several domains. reverseip.domaintools.comMar 7, 2020 at 21:10
- That IP seems to not be a server, and no domain is pointing to that IP.Mar 7, 2020 at 21:26
- Make sure to contact the RIR whois not the domain names ones.
The issue is that I can’t seem to find a way to get a domain name from the host name.
Because there isn’t or you are conflicting various things.
At the DNS level you may have a PTR record going from one IP address to a name. This is however not mandatory at all. See my full anwser for more details on this at
If we do it with your case, we do indeed have an answer, but that is not a generic rule:
Now since you are speaking about whois, you may think about something else.
etc.
Using The Command Line To Get An Ip Address Of A Web Resource
The most popular and frequently used command to get the IP address of the host is the ping command. The ping command initiates the exchange of packets with the selected host, and returns not only data about the host availability, but also provides the hosts IP address that will be displayed in square brackets after the hostname of the requested resource. Learn more about setting up a Ping/ICMP device with the Dotcom-Monitor platform.
Windows
To start the command line, in the search line type cmd and press Enter. This will open a command prompt. Then, select Command Prompt in the list.
In an open command line, type ping followed by the hostname . and press Enter. The command line will show the IP address of the requested web resource in the response.
An alternative way to call Command Prompt is the keyboard shortcut Win + R.
Linux
If you use a Linux operating system, then to run the console, use the Ctrl+Alt+T keyboard shortcut.
In the opened window, type in ping followed by a space and enter the hostname which IP address you want to receive. Then press Enter.
MAC OS
Also, on the Mac OS, you can use the Network Utility. Open Network Utility on the MAC and go to the ping tab. Enter the hostname and click the Ping button.
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How To Find The Ip Address Of A Website
To find an IP address on your computer, go to search and type in the command. In the command prompt enter the domain name. For example, enter www.yahoo.com. The system will show you the IP address of the domain. After which it will go to the site via different routes. Yes, when you want to visit a website on the internet. After your request is received by your ISP server and it gets the IP address of the domain you want to visit it will pick the route to take based on the different options it has.
Its like when we want to travel from point A to Point B and have multiple choices presented to us. We choose the route that suits us. The internet works in the same way. However, this information will only reveal the IP address of the domain and the different routes to it. This command will not disclose information regarding the host server location or domain owners details.
Another way of finding the IP address by entering the domain name is by using the ping command. Type ping domain name at the command prompt and it will reveal the IP address of the domain and send a packet of data four times to the IP address and show the time it took in milliseconds to send the packet. Again only the IP address is returned. The ping command is used by system administrators when they suspect that the response from their servers has slowed down.
Using The Ping Command
The ping utility is used to test for the reachability of a host via an ICMP echo request packet.
It comes preinstalled on many Linux distros, but if it doesnt come preinstalled on our Linux distro, we can then install it. We can use to install iputils-ping on Ubuntu/Debian or iputils-ping on RHEL.
Lets resolve a domain name to IP address by pinging the domain name:
$ ping baeldung.comPING baeldung.com 56 bytes of data.64 bytes from 104.26.13.74 : icmp_seq=1 ttl=32 time=11.1 ms
When we ping the domain baeldung.com, it replies with the IP address of 104.26.13.74, which is an A record of the domain baeldung.com.
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To Get Domain Name From Ip In Reverse Dns Dig
We get ip address :120.114.100.101 ,whose domain name is www.ksu.edu.tw .To get domain name from ip in Reverse DNS Dig
dig -x 120.114.100.101 +shortwww.ksu.edu.tw.
We get domain name : www.ksu.edu.tw ,whose ip address is 120.114.100.101.
dig smtp.mail.yahoo.com +shortsmtp.mail.global.gm0.yahoodns.net.106.10.150.171
We get ip address :106.10.150.171 ,whose domain name is smtp.mail.yahoo.com.
dig -x 106.10.150.171 +shortvcs-s-myc.mail.vip.sg3.yahoo.com.
why the result is not smtp.mail.yahoo.com as 106.10.150.171’s domain name?
- Most probably an issue with the DNS issue you have set up in resolv.conf. There is no issue when I try it and there is no 106.10.150.171 reported. You can conform this with “dig 8.8.8.8 smtp.mail.yahoo.com +short”
The simpliest answer: because it’s done so
You can create ptr to put to any dns name.
Do not need to follow the pattern:
A record --A-resolving--> ip addressip address --PTR-resolving--> A record
You can do so, but do not have to. You just need to have a PTR record.
The full answer:
Some mail servers have more than one domain. But you cannot create several PTR record to single ip*.
* see comments below
Check Domain Name Registration Using Python
To get started we will first import the required library and create a domain variable and pass the URL we want to get information about:
import whoisdomain='www.pyshark.com'
The usage of the functions of the python-whois library is very simple. Now, we know that www.pyshark.com exists since you are on this website and are reading this article.
To get an object that contains the WHOIS information about this domain name we need to use the following code:
domain_info = whois.whois
Note that this code will only execute successfully if the domain name is registered. If its not it will give you an error.
We can use this information to build a function that will simply return True/False is the domain name is registered/not registered:
def check_reg: try: domain_info = whois.whois return True except: return False
What this function will do is it will try to retrieve the WHOIS object with information about the domain name, and if it succeeds, it will return True. If not False which means that the domain name isnt registered.
Lets give it a try:
check_reg
and you should get:
True
What this result tells us is that it is a registered domain. For us this means that we can retrieve some information about it.
Now if you tried running this function against some random domain that doesnt exist, the function would return False which will mean that any further information retrieval of information is not possible simply because the domain isnt registered.
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