On a classic SysVinit system, which command prints the previous and the current runlevel, for example the output line 'N 3'?
LPIC-1 Exam 101-500, objective 101. System architecture easy
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The options
Not correct telinit
Wrong. telinit signals init to change to the runlevel given as its argument. It changes the runlevel instead of reporting it.
Correct runlevel
Correct. runlevel prints two fields, the previous runlevel and the current one; N in the first field means there has been no previous runlevel since boot.
Not correct chkconfig --list
Wrong. On Red Hat style systems chkconfig --list shows, per service, which runlevels it is switched on in. That is service configuration, not the current runlevel.
Not correct systemctl get-default
Wrong for a SysVinit system, and it answers a different question anyway: it prints the systemd target the machine boots into by default.
Why
Traditional runlevels: 0 halt, 1 single user, 6 reboot, with 2 to 5 defined by the distribution (Red Hat used 3 for text multi-user and 5 for graphical, Debian used 2 to 5 identically). systemd still emulates the runlevel command and maps runlevel3.target and runlevel5.target onto multi-user.target and graphical.target, so the command usually still answers on a modern system.
Where this comes from
- Cited
- LPI exam objective 101.3
- What it says
- Determining the current runlevel and changing it on SysVinit systems.
Practise this
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