Could not contact any CDS load balancers: https://rhui3.ap-south-1.aws.ce.redhat.com/pulp/content/ .
This error occurs due to the outdated package of the "RHUI-Client", this package helps to get access of the RHEL RHUI repositories.
If the version of "RHUI-Client" is below 3, then you can follow the action plan given below. To get the current version of "RHUI-Client" run the following command,
$ sudo rpm -q rh-amazon-rhui-client
As discussed, if the package version is below 3, run the following commands, once done try to perform any yum transaction,
$ sudo wget http://34.249.237.121/rh-amazon-rhui-client-3.0.31-1.el7.noarch.rpm
$ sudo yum localinstall rh-amazon-rhui-client-3.0.31-1.el7.noarch.rpm
$ sudo yum clean all
$ sudo yum repolist
This should resolve your first issue.
You may get the following message, while performing the yum transactions. This is because, the "subscription-manager" plugin is enabled,
This system is not registered with an entitlement server. You can use subscription-manager to register.
This^ is not an error, this is just a warning message and it can be ignored, you can disable the "subscription-manager" plugin using the following steps,
Open the following file using the following command,
# vim /etc/yum/pluginconf.d/subscription-manager.conf
You should get a similar line (as pasted below), in the file, it says "enabled=1" meaning, the subscription-manager plugin is enabled. To disable it, you need to put "enabled=0", and save it,
enabled=1. ==> Change it to zero "enabled=0"
Once done, run the following commands to confirm. Now, you should not get any "subscription-manager" warning messages,
$ sudo yum clean all
$ sudo yum repolist