When I switch from runlevel 3 to runlevel 1 on my CentOS 6 box the output of runlevel is 1 S:# runlevel1 SI'd expect the output to be 3 1. It's not a big deal but I'm keen to understand the logic behind the output. The man page for runlevel mentions that the Upstart init daemon works differently from SysVinit but as far as I'm aware runlevels 1 and S are always identical?
How can output of runlevel be 1 S?
centos;upstart;runlevel
According to the runlevel(7) manual page, 1 and S are distinct:Runlevel 1 is used to bring the system back down into single-user mode, after which the runlevel will be S.and the CentOS 7 runlevel manual page (which deprecates the feature), saysrunlevel prints the previous and current SysV runlevel if they are known.so S being current, and 1 being previous is consistent with the other version of the manual page.