I'm adapting scripts that configure PostgreSQL 9.6 and 10.x on Ubuntu 16.04 to also work on Centos 7.4. I'm missing the pg_conftool utility which allows me to identify and modify aspects of the PostgreSQL configuration in a clean, high-level fasion, and I get no results from yum whatprovides pg_conftool. What Yum package would I need to install to have it available?
pg_conftool isn't packaged by CentOS or EPEL. You could always check out the source yourself and use the included .spec file to build your own RPM.
There is no mention of
pg_conftool in the PostgreSQL documentation and I cannot find it in any of the CentOS packages. Given this, I expect this is a Debian/Ubuntu specific tool.
Of these, the tool pg_controldata seems the closest match to your use-case but the documentation only talks about retrieving cluster-wide configuration rather than setting it.
For setting data, you could modify the config files whilst using pg_ctl to stop, start, or reload the servers as required.
For CentOS, I don't have anything to hand that will give me file listings for the packages. If you aren't already, then I suggest that you use the official PostgreSQL repos rather than the default system repos.