Yum update fails on centos latest docker image

[srveerla]

yum update fails when i try to yum update as follows

FROM centos

MAINTAINER “sveerla”

RUN dnf clean all && rm -r /var/cache/dnf && dnf upgrade -y && dnf update -y

Error:

Errors during downloading metadata for repository ‘AppStream’:

• Curl error (6): Couldn’t resolve host name for http://mirrorlist.centos.org/?release=8&arch=x86_64&repo=AppStream&infra=container [Could not resolve host: mirrorlist.centos.org]
  Error: Failed to download metadata for repo ‘AppStream’: Cannot prepare internal mirrorlist: Curl error (6):

[wasim6624]

Same error i got >>>>>
Failed to set locale, defaulting to C.UTF-8
CentOS Linux 8 - AppStream 0.0 B/s | 0 B 00:10
Errors during downloading metadata for repository ‘appstream’:

• Curl error (6): Couldn’t resolve host name for http://vault.centos.org/centos/8/AppStream/x86_64/os/repodata/repomd.xml [Could not resolve host: vault.centos.org]
  Error: Failed to download metadata for repo ‘appstream’: Cannot download repomd.xml: Cannot download repodata/repomd.xml: All mirrors were tried