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Runlevels - Solaris vs Linux
Solaris and Linux both have runlevels. However the operational aspect are somewhat different. In this post we show the runlevels and describe the differences between them.
| Solaris | |
|---|---|
| Runlevel | Description |
| S, s | Single user mode. |
| 0 | Drop into firmware (ok prompt) |
| 1 | System Administrator mode. All local filesystems are mounted. Small set of essential system processes are running. Classed as an alternative single user mode. |
| 2 | Put the system in multi-user mode. All multi-user environment terminal processes and daemons are spawned but no network configured. |
| 3 | Extend multi-user mode by making local resources available over the network, and if configured start GUI. |
| 4 | Unused — Can be defined as an alternative multi-user environment configuration. |
| 5 | Shut the machine down so that it is safe to remove the power. If the hardware supports it, it will also romve the power. |
| 6 | Reboot |
| Linux | |
| Runlevel | Description |
| 0 | Reserved for the 'shutdown' phase. Entering init 0 from the shell prompt will shutdown the system and usually power off the machine. |
| 1 | Single-user mode, usually for very basic commands. This is the equivalent to 'safe mode' used by Windows. This level is usually only used to asses repairs or maintenance to the system. It does not allow users to login to the machine. |
| 2 | Used to start most of the machines services. However, it does not start the network file sharing service (SMB, NFS). This will allows multiple users to login to the machine. |
| 3 | Loads all services except the X windows system — This means the system will boot to the equivalent of DOS. No GUIs (KDE, Gnome) will start. This level allows multiple users to login to the machine. |
| 4 | Custom level — By default it will start a few more services than level 3. This level is usually only used under special circumstances. |
| 5 | Multi-user mode — This will start any GUIs, extra services for printing, and 3rd party services. This runlevel is generally used on by workstations. |
| 6 | Reserved for 'reboot' only. Be carefully when running this command. Once you have entered 'init 6', there is no stopping it! |