On 17Dec2017 18:05, sam varshavchik <mrsam(a)courier-mta.com> wrote:
But I really don't understand why so much research is needed for
this issue,
by disabling random things, and then trying other random things. Either
NetworkManager-wait-online actually waits until the network interfaces have
their IP address set, or it doesn't. If it's supposed to do it, then it should
be possible to isolate the issue without turning it off completely and
switching to a completely different network configuration infrastructure. If
it's not supposed to do it, then what exactly is it supposed to be doing,
anyway?
Someone pointed out that it seems to wait for the network services to start,
not for the IP assignments/allocation to complete.
As a scenario, consider dhclient. It typically tries to conduct an initial DHCP
negotiation, but after a little while backgrounds itself (and continues to
try).
What is your desired behaviour when DHCP service is not available? Have your
system boot hang until it is? For a home LAN that might be tenable, _if_ you
are always physically there to remedy things if necessary. (Of course, if my
laptop needs to come up before I can easily remedy things I have a problem.)
But when DHCP comes from one's ISP (be that a real ISP or some LAN you don't
personally manage)?
Just outlining why NetworkManager-wait-online may not be doing what people had
hoped. Instead, it may be doing what is reasonable, and its completion doesn't
imply what people are needing for their next stuff.
Myself, I start far more than I used to as services via my own account, and
some of those services defer their startup until I have a default route, a fair
proxy for having the network "up". They all monitor a flag and I have a little
script to watch for a default route. Conversely, they also shutdown if that
flag goes false.
I'm not trying to defend systemd here, just saying that (a) it isn't
necessarily unreasonable for NetworkManager-wait-online to not imply the
condition people thought and that (b) I personally take more things on myself,
the better to be independent of systemd or whatever other quaint fashions my
distro may follow.
Cheers,
Cameron Simpson <cs(a)cskk.id.au> (formerly cs(a)zip.com.au)