[CentOS-virt] Xen runlevels 5.3 vs. 5.4

Stephen John Smoogen smooge at gmail.com
Mon Nov 16 19:47:52 UTC 2009

On Mon, Nov 16, 2009 at 11:41 AM, Ben M. <centos at rivint.com> wrote:
> I just notice that my 5.3 (updated to 5.4) Centos Xen stock install has
> different runlevels that my from scratch 5.4 install box.
> 5.3 --> 5/4
> xend            0:off   1:off   2:on    3:on    4:on    5:on    6:off
> xendomains      0:off   1:off   2:on    3:on    4:on    5:on    6:off
> 5.4 "pure"
> xend            0:off   1:off   2:on    3:on    4:on    5:on    6:off
> xendomains      0:off   1:off   2:off   3:on    4:on    5:on    6:off
> Should Level 2 on xendomains be on or off?

Ok I think the following is correct, but I don't have my notes
available to compare with at the moment (and google is having issues
for me (though gmail is working great)).

Runlevel 2 in the Red Hat/CentOS/Fedora control system is different
from other operating systems and some other Linux's. Where some OS's
will use boot levels as stages to run in (you have to go through 1 to
get to 2), Linux operating systems in general considers them as
seperate ways to start up an OS. And each Linux OS family has its own
way of defining what they mean.

In the end, the important question is "Do you run at Runlevel 2?"
Runlevel 2 and 4 are rarely used and each has different site
definitions of what its being used for. Some sites use runlevel2 as
multi-user/no-network, and other sites use it for multi-user/debugging
(eg runlevel 3 but some changes to see what might have broken when we
turned on X). Runlevel 4 is similarly used (eg its up to a site to
define how they want to use it). I think Red Hat normally defines
their runlevel 2 as multi-user/no-network which would mean xendomains
should be off... however its probably

Stephen J Smoogen.

Ah, but a man's reach should exceed his grasp. Or what's a heaven for?
-- Robert Browning

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