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Could we put a comment in /etc/crontab alerting sysadmins that a new scheduling system is also active? I think that will reduce migration pain. Something like:

# Note that many services use systemd calendar timers to schedule periodic tasks. Run the command
# systemctl [whatever would be the right thing to run]
# to list active timers.

? --Mattdm (talk) 20:20, 6 February 2013 (UTC)