SLE 11 does not ship systemd and then using systemctl poweroff does not
work. Therefore we fall back to using /sbin/shutdown for machines without
systemd.
This fixes https://github.com/hashicorp/vagrant/issues/12487
We have started seeing occasional shutdown failures on openSUSE Tumbleweed with
Virtualbox inside a qemu virtual machine, where `shutdown -h now` would return
nil. While the machine is successfully turned off, the command fails and vagrant
reports an error.
This commit changes the shutdown command to launch in the background which
also triggers a shutdown, but always succeeds.
getent queries the system resolver for the hostname - but it's not
the resolver we're interested in. In fact, the hostname-to-be-set
may already exist in DNS (becuase DNS really is a nifty thing and
can do a lot of things which are not that possible with /etc/hosts
alone), in which case getent will "not fail" and vagrant will believe
the hostname had already been set.
Instead, query hostnamectl for the "static" hostname - that's the
one we will be setting, so we're ok IFF hostnamectl returns exactly
what we would be setting.
- nfs.service got recently removed in openSUSE Tumbleweed and calling service
restart nfs errors out on Tumbleweed. nfs.service has been an alias to
nfs-client.target for a very long time and can thus be safely substituted.
- all actively supported versions of openSUSE & SLE are using systemd now
=> no reason not to use systemctl
