Creating Users & Groups (CentOS) - wollardj/Mandrill GitHub Wiki
When Mandrill is launched as a root process and the
MANDRILL_MODE environment variable is set to 'production', the startup code will automatically attempt to become the
_mandrill user by calling
setuid on its own process. This is currently hard-coded, but may be configurable some day.
sudo groupadd --system munki
sudo adduser --system _mandrill -G munki
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