| sysvinit command | systemd command | notes |
| service sshd start | systemctl start sshd | Start the sshd service |
| service sshd stop | systemctl stop sshd | Stop the sshd service |
| service sshd restart | systemctl restart sshd | Restart the sshd service |
| service sshd reload | systemctl reload sshd | Reload the sshd service |
| service sshd condrestart | systemctl condrestart sshd | Restarts sshd if it’s already running |
| service sshd status | systemctl status sshd | Check the status of sshd |
| chkconfig –list | systemctl list-unit-files –type=service | List all services and their status |
| chkconfig sshd on | systemctl enable sshd | Enable the sshd service |
| chkconfig sshd off | systemctl disable sshd | Disable the sshd service |
| chkconfig –list sshd | ls /etc/systemd/system/*.wants/sshd.service | Show all runlevels/targets sshd is enabled in |
| chkconfig –add sshd | systemctl daemon-reload | Used to create new service files |
sysvinit service scripts are stored in /etc/init.d or /etc/rc.d/init.d and have no extension.
systemd service files are stored in /etc/systemd/system/*.wants directories. Service files need to have a .service extension.
Runlevels
| sysvinit runlevel | systemd target name | notes |
| 0 | runlevel0, poweroff | Shut down and power off the system |
| 1 | runlevel1, rescue | Setup rescue shell |
| 2, 3, 4 | runelevel2, runlevel3, runlevel4, multi-user | Non-graphical multi-user |
| 5 | runlevel5, graphical | Graphical multi-user |
| 6 | runlevel6, reboot | Reboot the system |
Commands
| sysvinit | systemd | notes |
| runlevel | systemctl list-units –type target | List runlevels |
| cat /etc/inittab | systemctl get-default | Default runlevel |
| telinit <runlevel#> | systemctl isolate <name>.target | Change the runlevel |
| nano or vi /etc/inittab | systemctl set-default <name>.target | Change the default runlevel |