Re: [developer] Review - 15665 svc:/network/loopback exits successfully even if it fails

[Alan Coopersmith <alan.coopersmith@oracle.com>]

On 7/26/24 08:14, Peter Tribble wrote:
> As I mentioned in my other reply, it seems that what we're after is some way to mark
> a service as having generated an error without bringing the system down by going
> into maintenance. Some sort of degraded mode.
> 
> So the equivalent of SMF_EXIT_DEGRADED might be what we're looking for?

SMF_EXIT_DEGRADED was added in Solaris 11.4, but the degraded mode existed long
before that - see for instance smf_degrade_instance() on
https://illumos.org/man/3SCF/smf_degrade_instance and the states section of
https://illumos.org/man/7/smf .

The addition of SMF_EXIT_DEGRADED allows start, stop, and refresh methods to
put the service into degraded mode, since otherwise they'd have to return an
exit code that put the service into one of the other modes (online, offline,
maintenance), and then have something else wait for the method to finish and
then call smf_degrade_instance(), which could lead to race conditions or
incorrect actions being taken during the brief moment the service is in the
wrong state before going to degraded mode.

	-alan-