If that is the case, why do you run CentOS 7 on the server? You can stay with CentOS 6 for now and either wait till Linux systemd-free distribution mature enough to be run on server is available. Which it almost is: Devuan (systemd-free fork of Debian) has released "alpha" version about half a year ago. If you feel "married" to Linux, maybe it is a good idea to play with Devuan, provide them feedback thus helping them to become system-free Linux acceptable for servers. Simultaneously you can explore other options which would be to migrate away from Linux (Open Solaris, FreeBSD, NetBSD, OpenBSD will be much smaller step than stepping up to CentOS 7 - that is my experience, though FreeBSD migration of servers I started came much earlier than CentOS 7 and for different reason).
If I had the choice... The OS and the version are decreed by the contractor, I'm just a maintainer.
Sylvain. Pensez ENVIRONNEMENT : n'imprimer que si ncessaire