Centos7 Docker Image, Mirrors failing for arm64 & ppc64le

[steelhead31]

Centos 7 based elements in the dockerfile are failing due to mirrorlist.centos.org no longer being valid. This has been rectified for x64, however issues are being encountered on arm64 and ppc64le

Loaded plugins: fastestmirror, ovl
14Determining fastest mirrors
15Could not retrieve mirrorlist http://mirrorlist.centos.org/?release=7&arch=x86_64&repo=os&infra=container error was
1614: curl#6 - "Could not resolve host: mirrorlist.centos.org; Unknown error"
17
18
19 One of the configured repositories failed (Unknown),
20 and yum doesn't have enough cached data to continue. At this point the only
21 safe thing yum can do is fail. There are a few ways to work "fix" this:
22
23 1. Contact the upstream for the repository and get them to fix the problem.
24
25 2. Reconfigure the baseurl/etc. for the repository, to point to a working
26 upstream. This is most often useful if you are using a newer
27 distribution release than is supported by the repository (and the
28 packages for the previous distribution release still work).
29
30 3. Run the command with the repository temporarily disabled
31 yum --disablerepo=<repoid> ...