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I have a fresh install of latest centos 7

[root@localhost ~]# cat /etc/centos-release
CentOS Linux release 7.4.1708 (Core) 
[root@localhost ~]# 

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.

[root@localhost ~]# yum update
Loaded plugins: fastestmirror
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=stock error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
http://mirror.centos.org/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirror.centos.org; Unknown error"
Trying other mirror.

 One of the configured repositories failed (CentOS-7 - Base),
 and yum doesn't have enough cached data to continue. At this point the only
 safe thing yum can do is fail. There are a few ways to work "fix" this:

     1. Contact the upstream for the repository and get them to fix the problem.

     2. Reconfigure the baseurl/etc. for the repository, to point to a working
        upstream. This is most often useful if you are using a newer
        distribution release than is supported by the repository (and the
        packages for the previous distribution release still work).

     3. Run the command with the repository temporarily disabled
            yum --disablerepo=base ...

     4. Disable the repository permanently, so yum won't use it by default. Yum
        will then just ignore the repository until you permanently enable it
        again or use --enablerepo for temporary usage:

            yum-config-manager --disable base
        or
            subscription-manager repos --disable=base

     5. Configure the failing repository to be skipped, if it is unavailable.
        Note that yum will try to contact the repo. when it runs most commands,
        so will have to try and fail each time (and thus. yum will be be much
        slower). If it is a very temporary problem though, this is often a nice
        compromise:

            yum-config-manager --save --setopt=base.skip_if_unavailable=true

failure: repodata/repomd.xml from base: [Errno 256] No more mirrors to try.
http://mirror.centos.org/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirror.centos.org; Unknown error"
[root@localhost ~]# 

So when I list the repos I get this:

[root@localhost ~]# yum repolist all
Loaded plugins: fastestmirror
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=stock error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
http://mirror.centos.org/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirror.centos.org; Unknown error"
Trying other mirror.
http://mirror.centos.org/centos/7/os/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirror.centos.org; Unknown error"
Trying other mirror.
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=centosplus&infra=stock error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
http://mirror.centos.org/centos/7/centosplus/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirror.centos.org; Unknown error"
Trying other mirror.
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=extras&infra=stock error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
http://mirror.centos.org/centos/7/extras/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirror.centos.org; Unknown error"
Trying other mirror.
Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=updates&infra=stock error was
14: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
http://mirror.centos.org/centos/7/updates/x86_64/repodata/repomd.xml: [Errno 14] curl#6 - "Could not resolve host: mirror.centos.org; Unknown error"
Trying other mirror.
repo id                                                                                         repo name                                                                                         status
C7.0.1406-base/x86_64                                                                           CentOS-7.0.1406 - Base                                                                            disabled
C7.0.1406-centosplus/x86_64                                                                     CentOS-7.0.1406 - CentOSPlus                                                                      disabled
C7.0.1406-extras/x86_64                                                                         CentOS-7.0.1406 - Extras                                                                          disabled
C7.0.1406-fasttrack/x86_64                                                                      CentOS-7.0.1406 - CentOSPlus                                                                      disabled
C7.0.1406-updates/x86_64                                                                        CentOS-7.0.1406 - Updates                                                                         disabled
C7.1.1503-base/x86_64                                                                           CentOS-7.1.1503 - Base                                                                            disabled
C7.1.1503-centosplus/x86_64                                                                     CentOS-7.1.1503 - CentOSPlus                                                                      disabled
C7.1.1503-extras/x86_64                                                                         CentOS-7.1.1503 - Extras                                                                          disabled
C7.1.1503-fasttrack/x86_64                                                                      CentOS-7.1.1503 - CentOSPlus                                                                      disabled
C7.1.1503-updates/x86_64                                                                        CentOS-7.1.1503 - Updates                                                                         disabled
C7.2.1511-base/x86_64                                                                           CentOS-7.2.1511 - Base                                                                            disabled
C7.2.1511-centosplus/x86_64                                                                     CentOS-7.2.1511 - CentOSPlus                                                                      disabled
C7.2.1511-extras/x86_64                                                                         CentOS-7.2.1511 - Extras                                                                          disabled
C7.2.1511-fasttrack/x86_64                                                                      CentOS-7.2.1511 - CentOSPlus                                                                      disabled
C7.2.1511-updates/x86_64                                                                        CentOS-7.2.1511 - Updates                                                                         disabled
C7.3.1611-base/x86_64                                                                           CentOS-7.3.1611 - Base                                                                            disabled
C7.3.1611-centosplus/x86_64                                                                     CentOS-7.3.1611 - CentOSPlus                                                                      disabled
C7.3.1611-extras/x86_64                                                                         CentOS-7.3.1611 - Extras                                                                          disabled
C7.3.1611-fasttrack/x86_64                                                                      CentOS-7.3.1611 - CentOSPlus                                                                      disabled
C7.3.1611-updates/x86_64                                                                        CentOS-7.3.1611 - Updates                                                                         disabled
base/7/x86_64                                                                                   CentOS-7 - Base                                                                                   enabled: 0
base-debuginfo/x86_64                                                                           CentOS-7 - Debuginfo                                                                              disabled
base-source/7                                                                                   CentOS-7 - Base Sources                                                                           disabled
c7-media                                                                                        CentOS-7 - Media                                                                                  disabled
centosplus/7/x86_64                                                                             CentOS-7 - Plus                                                                                   enabled: 0
centosplus-source/7                                                                             CentOS-7 - Plus Sources                                                                           disabled
cr/7/x86_64                                                                                     CentOS-7 - cr                                                                                     disabled
extras/7/x86_64                                                                                 CentOS-7 - Extras                                                                                 enabled: 0
extras-source/7                                                                                 CentOS-7 - Extras Sources                                                                         disabled
fasttrack/7/x86_64                                                                              CentOS-7 - fasttrack                                                                              disabled
updates/7/x86_64                                                                                CentOS-7 - Updates                                                                                enabled: 0
updates-source/7                                                                                CentOS-7 - Updates Sources                                                                        disabled
repolist: 0
[root@localhost ~]# 

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

my /etc/yum.repos.d/CentOS-Base.repo

# CentOS-Base.repo
#
# The mirror system uses the connecting IP address of the client and the
# update status of each mirror to pick mirrors that are updated to and
# geographically close to the client.  You should use this for CentOS updates
# unless you are manually picking other mirrors.
#
# If the mirrorlist= does not work for you, as a fall back you can try the 
# remarked out baseurl= line instead.
#
#

[base]
name=CentOS-$releasever - Base
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=os&infra=$infra
baseurl=http://mirror.centos.org/centos/$releasever/os/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

#released updates 
[updates]
name=CentOS-$releasever - Updates
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=updates&infra=$infra
baseurl=http://mirror.centos.org/centos/$releasever/updates/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

#additional packages that may be useful
[extras]
name=CentOS-$releasever - Extras
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=extras&infra=$infra
baseurl=http://mirror.centos.org/centos/$releasever/extras/$basearch/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7

#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-$releasever - Plus
mirrorlist=http://mirrorlist.centos.org/?release=$releasever&arch=$basearch&repo=centosplus&infra=$infra
baseurl=http://mirror.centos.org/centos/$releasever/centosplus/$basearch/
gpgcheck=1
enabled=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-7
Albano Albanese
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  • for users visiting later: we also started getting this error albeit due to a totally different reason - the mirrorlist link of ius has been migrated to a new endpoint and most of our servers had the old one configured due to which the failure occurred with a similar error message. refer: https://github.com/iusrepo/infrastructure/issues/14 – 6harat Jan 09 '20 at 05:25
  • It happened to be and found out that setting enabled from 1 to 0 inside /etc/yum.repos.d/endpoint.repo file fixed the error. – ewalel Apr 13 '22 at 13:24

3 Answers3

35
Could not resolve host: mirrorlist.centos.org; Unknown error

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 8.8.8.8. If this fails, try ping <local-gateway-ip>. If that also fails, your local network configuration is wrong and you'll have to check the configuration.

If you can ping 8.8.8.8, 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.

UPDATE

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):

nameserver 9.9.9.9

Save this file, then try yum update again.

You can also try other DNS hosts if you would rather, such as 8.8.8.8 or 8.8.4.4 or any of the OpenDNS hosts.

Andrew
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  • etc/resolv.conf is empty I didnt touch anything there – Albano Albanese Mar 23 '18 at 20:23
  • I tried this http://utdream.org/post.cfm/yum-couldn-t-resolve-host-mirrorlist-centos-org-for-centos-6 and this one https://access.redhat.com/solutions/1433223 also your 9.9.9.9 but no luck :( – Albano Albanese Mar 23 '18 at 20:50
  • If you add a DNS resolver to `/etc/resolv.conf` and still can't do a `host google.com` then you need to check your local network configuration. Post the output of `ip addr` and `ip route` and make sure to include information regarding the local network. Also, you may have to bring the NIC up with `ip link set up`. You may also want to post the output of `iptables -nL` to ensure you don't have a bad Firewall configuration blocking your connections. – Andrew Mar 23 '18 at 20:51
  • updated my question with the outputs you can check? Thankyou for your help this is very important for me because I have a ranked website which is offlinel. – Albano Albanese Mar 23 '18 at 21:03
  • From what I see, I'm wondering if the firewall isn't configured right, but it looks fine from here. What's the output of `host google.com 8.8.8.8`? And what do you see when you try `ping 8.8.8.8`? Everything _looks_ ok, but something isn't quite right and I'm not sure what. – Andrew Mar 23 '18 at 21:28
  • -bash: host: command not found ping 8.8.8.8 is responding fine – Albano Albanese Mar 23 '18 at 22:09
  • What about `ping google.com`? Your network stack is fine, but the DNS resolution seems busted. Also, what is the output of `cat /etc/resolv.conf` – Andrew Mar 23 '18 at 22:13
  • ping: google.com: Name or service not known, there is no messagge for cat /etc/resolv.conf its very strange and thankyou very much for the help – Albano Albanese Mar 23 '18 at 22:33
  • You need to edit the file as I stated in my updated answer. You need to open the file in something like `nano` or `vi`, then add a line `nameserver 9.9.9.9`, then save the file. Then try the `ping google.com` command. You might have to use `sudo vi` or `sudo nano` if you aren't logged in as `root` already. – Andrew Mar 23 '18 at 22:35
  • Andrew you are great and your help is very appreciated but I edited files via sftp using filezilla, today I tried with vi command in terminal and it says read only file, so when I try with nano says that command not found lol its driving me to be a crazy boy I didnt sleep all the night just for this problem and still can't find a solution :( – Albano Albanese Mar 24 '18 at 06:49
  • fount it and worked :D https://ubuntuforums.org/archive/index.php/t-1509499.html thankyou thankyou thankyou ! – Albano Albanese Mar 24 '18 at 06:54
4

You may have a connectivity issue somewhere, here a small process to check where you have an issue.

Basic Connectivity

Check if the server has internet (ip address and correct route - if not working, check with ip address if you have an IP address).

 ping 8.8.8.8

Resolver

Check what are the resolver and ping them

 cat /etc/resolv.conf

You should have line with nameserver and an IP address. Check that IP is answering.

 ping xx.xx.xx.xx

Then do an nslookup

 nslookup mirrorlist.centos.org

It should return a list of IP addresses. If not, your DNS server might not working correctly, you can try another server with

 nslookup
 > server 8.8.8.8
 > mirrorlist.centos.org

And check this time it's working as expected.

ob2
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  • Hey Oliver thankyou for the reply my resolv.conf is empty there is nothing and when I ping 8.8.8.8 is giving the response. – Albano Albanese Mar 23 '18 at 20:17
  • is there anything that I can add in resolv.conf? If I can get the yum working the first I will in stall wget and after than virtualmin but as I said resolv.conf doesnt have anything inside – Albano Albanese Mar 23 '18 at 20:19
  • I have also tried this https://access.redhat.com/solutions/1433223 but same issue after reboot so the updated package is there but no luck the error is same – Albano Albanese Mar 23 '18 at 20:33
  • try adding a line looks like `nameserver 8.8.8.8` – ob2 Mar 23 '18 at 20:34
  • nothing happens :( – Albano Albanese Mar 23 '18 at 20:38
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    Are you sure you're online? That was my problem... During install I connected to wifi, signed in, was online... but the signal dropped without my noticing and I saw these errors. If you can't ping 8.8.8.8, you are likely offline. Sounds obvious... but it isn't if you don't notice. – cssyphus Apr 02 '20 at 12:53
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    We still face this problem in 2020..., from RHEL/CentOS side no action taken – csavvy Oct 06 '20 at 10:12
0

I had this issue in centos streams and had to click on networks on the top bar and connect wired network.

user3520245
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