i have a little problem. I am using Windows in the company and have to install docker. That’s why i have installed Oracle Virtual Box and CentOS 7. Now i need to install Docker. I am reading the following instructions from this site: https://www.kinamo.be/en/support/faq/installing-docker-engine-on-centos-7

But i have the first problem at step 1 and this command: $ sudo yum update

I get this error message immediately:

I tried setting up a DNS Lookup on CentOS 7 (in a Virtual Box VM), which works for FQDN on the same virtual machine as the DNS. However when I try to resolve the short hostname, it fails.

I have seen this working on some servers and wanted to learn how to set it up myself. Appreciate any help on this.

Below are the configurations in place:

Command Output

NS Lookup on FQDN

Now all the commands (nslookup, dig and host) fail on the short hostname.

I know there is something missing/wrong in my configuration, but am not able to figure out what.

1 Answer 1

The problem is in your resolv.conf /DHCP configuration if resolv.conf is not static.

You have got to add to the search directive of resolv.conf the domain eai.com

When you try a DNS name lookup, the resolver libraries, if unsuccessful, try in turns to resolve the name adding the domains in the search directive until they find a resolvable name, or until they exhaust the domain list in the search directive.

I have a fresh install of latest centos 7

I wanted to install something and wget was not installed so when I tried to install wget I saw tha yum is giving error.

I saw maybe all the topics about this problem on the internet but no luck I cant find my solution.

So when I list the repos I get this:

Im not sure where can be the problem its a fresh install on my vmware/OVH dedicated server.

I have another server installed and working fine but this time I got this problem .

Any one can help me?I have also tried to enable all disabled lines in etc/yum.repo.d

2 Answers 2

This indicates that you either (a) don’t have a properly configured DNS server or (b) your network configuration isn’t correct and you can’t connect to a DNS server to check the hostname mirrorlist.centos.org .

Try using ping . If this fails, try ping . If that also fails, your local network configuration is wrong and you’ll have to check the configuration.

If you can ping , try using host , nslookup or dig to check the DNS settings like host google.com or dig google.com . If these fail, you need to check your DNS settings. Check /etc/resolv.conf to see what’s configured.


Since /etc/resolv.conf is blank, you need to setup a DNS resolver. I would suggest entering the following into the file using nano or vi (or whatever your comfortable using):

Save this file, then try yum update again.

You can also try other DNS hosts if you would rather, such as or or any of the OpenDNS hosts.