Googling "redhat-ppc7" doesn't really return any meaningful explanation. What is redhat=ppc7 and what is the difference between redhat-ppc7 and redhat7 ?
This is the output from one of the ppc nodes.
[root@hdp-test-4 ~]# uname -a Linux hdp-test-4 3.10.0-693.el7.ppc64le #1 SMP Thu Jul 6 19:59:44 EDT 2017 ppc64le ppc64le ppc64le GNU/Linux
Here you can find ppc64le , whereas in your output it is x86_64. 64 denotes 64bit OS.