1 config files in 39 etc 39 need updating
For example, in case of contains three numerical values.
The most important is the first number that represents the default runlevels in which the service is started.
Before taking time to convert a Sys V init script to a unit file, make sure that the conversion was not already done elsewhere.
All core services installed on Red Hat Enterprise Linux 7 come with default unit files, and the same applies for many third-party software packages.
See Section 9.6.5, “Working with Instantiated Units” for details.
This is translated as an ordering dependency, boot facility names are replaced with unit file names of corresponding services or targets they belong to.
Note that the graphical.target depends on multiuser.target, therefore it is not necessary to specify both, as in Example 9.17, “postfix.service Unit File”.
You might find information on default and forbidden runlevels also at The other two values specified on the #chkconfig line represent startup and shutdown priorities of the init script.
Use Table 9.6, “Comparison of Sys V Runlevels with systemd Targets” to map these runlevels to equivalent systemd targets.
Then list these targets in the was previously started in runlevels 2, 3, 4, and 5, which translates to multi-user.target and graphical.target on Red Hat Enterprise Linux 7.