Get ip from domain linux

You can see the IP address of the website in the ‘ANSWER SECTION’.

Facebook has tons of servers and you may see a different IP address based on your geo-location and time. You shouldn’t find it unusual.

Method 2: Use nslookup command to find IP address of website in Linux

Like Dig, nslookup command is also used for querying the DNS records. nslookup stands for ‘name server lookup’.

You might need to install nslookup. If you have sudo access, you can use your Linux distribution’s installation command to install this tool. On Debian and Ubuntu, the command below will install nslookup:

sudo apt install nslookup

Once you have the tool, just use it in the following fashion:

For example, if I try to get the IP address of Facebook.com, this is the output I get:

nslookup facebook.com Server: 127.0.0.53 Address: 127.0.0.53#53 Non-authoritative answer: Name: facebook.com Address: 157.240.25.35 Name: facebook.com Address: 2a03:2880:f10c:83:face:b00c:0:25de

Method 3: Get IP address of website using host command

Like the above two, host is also a DNS lookup utility. But unlike the above two commands, the output of the host command is neat and precise. It just displays the IPv4 and IPv6 addresses of a website.

Sample output would be like this:

host facebook.com facebook.com has address 157.240.13.35 facebook.com has IPv6 address 2a03:2880:f139:83:face:b00c:0:25de facebook.com mail is handled by 10 msgin.vvv.facebook.com.

Method 4: Get website’s IP address with ping command in Linux

Let’s see how to get the IP address of a website with the ping command in Linux.

Ping command is used to check whether the remote host is up or not. You can use either the server’s IP address or the URL. The syntax is pretty much the same.

A sample output for facebook.com looks like this:

ping facebook.com PING facebook.com (157.240.24.35) 56(84) bytes of data. 64 bytes from edge-star-mini-shv-01-sin2.facebook.com (157.240.24.35): icmp_seq=1 ttl=52 time=203 ms 64 bytes from edge-star-mini-shv-01-sin2.facebook.com (157.240.24.35): icmp_seq=2 ttl=52 time=163 ms 64 bytes from edge-star-mini-shv-01-sin2.facebook.com (157.240.24.35): icmp_seq=3 ttl=52 time=248 ms ^C --- facebook.com ping statistics --- 4 packets transmitted, 3 received, 25% packet loss, time 3001ms rtt min/avg/max/mdev = 163.965/205.339/248.902/34.713 ms

You’ll have to use Ctrl+C to stop the ping command.

Conclusion

So, you just saw three networking tools that would give you the same result. I hope this quick Linux tip helped you find a website's IP address in Linux terminal.

If you have any questions or suggestions, please leave a comment below. Don’t forget to subscribe to the newsletter and get all the new tutorials in your inbox, for free.

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Get ip address from hostname in C with Linux sockets

Socket applications often need to convert hostnames like google.com to their corresponding ip address. This is done through dns requests.

The socket api in linux provides functions like gethostbyname and getaddrinfo that can be used to perform the dns requests and get the ip address.

1. gethostbyname

The first method uses the traditional gethostbyname function to retrieve information about a hostname/domain name.

#include //printf #include //memset #include //for exit(0); #include #include //For errno - the error number #include //hostent #include int hostname_to_ip(char * , char *); int main(int argc , char *argv[]) < if(argc <2) < printf("Please provide a hostname to resolve"); exit(1); >char *hostname = argv[1]; char ip[100]; hostname_to_ip(hostname , ip); printf("%s resolved to %s" , hostname , ip); printf("\n"); > /* Get ip from domain name */ int hostname_to_ip(char * hostname , char* ip) < struct hostent *he; struct in_addr **addr_list; int i; if ( (he = gethostbyname( hostname ) ) == NULL) < // get the host info herror("gethostbyname"); return 1; >addr_list = (struct in_addr **) he->h_addr_list; for(i = 0; addr_list[i] != NULL; i++) < //Return the first one; strcpy(ip , inet_ntoa(*addr_list[i]) ); return 0; >return 1; >

$ gcc hostname_to_ip.c && ./a.out www.google.com www.google.com resolved to 74.125.235.16 $ gcc hostname_to_ip.c && ./a.out www.msn.com www.msn.com resolved to 207.46.140.34 $ gcc hostname_to_ip.c && ./a.out www.yahoo.com www.yahoo.com resolved to 98.137.149.56

2. getaddrinfo

The second method uses the getaddrinfo function to retrieve information about a hostname/domain name. The getaddrinfo supports ipv6 better.

#include //printf #include //memset #include //for exit(0); #include #include //For errno - the error number #include //hostent #include int hostname_to_ip(char * , char *); int main(int argc , char *argv[]) < if(argc <2) < printf("Please provide a hostname to resolve"); exit(1); >char *hostname = argv[1]; char ip[100]; hostname_to_ip(hostname , ip); printf("%s resolved to %s" , hostname , ip); printf("\n"); > /* Get ip from domain name */ int hostname_to_ip(char *hostname , char *ip) < int sockfd; struct addrinfo hints, *servinfo, *p; struct sockaddr_in *h; int rv; memset(&hints, 0, sizeof hints); hints.ai_family = AF_UNSPEC; // use AF_INET6 to force IPv6 hints.ai_socktype = SOCK_STREAM; if ( (rv = getaddrinfo( hostname , "http" , &hints , &servinfo)) != 0) < fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(rv)); return 1; >// loop through all the results and connect to the first we can for(p = servinfo; p != NULL; p = p->ai_next) < h = (struct sockaddr_in *) p->ai_addr; strcpy(ip , inet_ntoa( h->sin_addr ) ); > freeaddrinfo(servinfo); // all done with this structure return 0; >

$ gcc hostname_to_ip.c && ./a.out www.google.com www.google.com resolved to 74.125.235.19 $ gcc hostname_to_ip.c && ./a.out www.yahoo.com www.yahoo.com resolved to 72.30.2.43 $ gcc hostname_to_ip.c && ./a.out www.msn.com www.msn.com resolved to 207.46.140.34

A Tech Enthusiast, Blogger, Linux Fan and a Software Developer. Writes about Computer hardware, Linux and Open Source software and coding in Python, Php and Javascript. He can be reached at [email protected] .

17 Comments

1. thisisbazz August 17, 2014 at 6:06 am Actually, having learned a little more, I’ve reverted to the newer inet_ntop. Simpler to use, I’m unsure if any power is lost from using it. I think it will be alright. Just thought I would leave evidence of my trail.

1. Silver MoonMarch 23, 2013 at 10:10 pm try changing the following line hints.ai_family = AF_UNSPEC; // use AF_INET6 to force IPv6 to this hints.ai_family = AF_INET;

1. Yu Jing March 24, 2013 at 4:04 am Thank you, It works !
   In the manual,
   “The value AF_UNSPEC indicates that getaddrinfo() should return socket addresses for any address family (either IPv4 or IPv6, for example) that can be used with node and service.”
   What is the basis of the judgments using IPv4 or IPv6? The server support ipv6 ？ or just my pc support IPv6?

1. Yu Jing March 26, 2013 at 8:08 am Thanks for your patient , while ,what makes me confuse is … I mean,
   if the ai_family’s value is “AF_UNSPEC”, how the code judge using IPv4 or IPv6 ? For example , if only my pc support IPv6 , will the code trying return the IPv6 address ?

1. Silver MoonMarch 6, 2013 at 9:09 pm check your internet connectivity by pinging the host first.
   use the following command at terminal/console ping hostname if ping replies come correctly, then try the program again and let me know the results.

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