On the proxy:
- 
yum group install "Development Tools"
 - 
yum install rh-ruby27-ruby-devel
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scl enable tfm bash
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yum install sqlite-dev
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gem install sqlite
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gem build smart_proxy_container_gateway.gemspec
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gem install smart_proxy_container_gateway-x.x.x.gem
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edit /etc/foreman-proxy/settings.d/container_gateway.yml: