On Wed, Apr 08, 2020 at 04:18:32PM +0200, Thomas HUMMEL wrote: > Hello, thanks for your answer > > On 4/8/20 10:25 AM, Beniamino Galvani wrote: > > >> - step2 (I guess) puts HOSTNAME=maestro-1000 in /etc/sysconfig/network > > > > AFAIK, NetworkManager doesn't do that. > > Although I saw that it was the postscript which wrote into this file, I > thought NetworkManager was considering it because it is mentionned in man 5 > nm-settings-ifcfg-rh
Yes, the file is used for other variables but not for HOSTNAME. > > Yes, it uses the SetHostname D-Bus call of systemd-hostnamed, which > > changes the transient (kernel) hostname. > > Talking about D-Bus, I see this in the begining of all 3 (default, none, > dhcp) traces : > > Apr 08 14:53:29 maestro-1000.maestro.pasteur.fr NetworkManager[25235]: > <trace> [1586350409.2521] policy: get-hostname: > "maestro-1000.maestro.pasteur.fr" (from dbus) > Apr 08 14:53:29 maestro-1000.maestro.pasteur.fr NetworkManager[25235]: > <trace> [1586350409.2521] policy: hostname-original: set to > "maestro-1000.maestro.pasteur.fr" > > how is this hostname fully qualified who sets it ? The original hostname > always seems to be this one. I don't know, it is set before NM starts. > >> a) default : what's described above (fqdn) > >> b) none : hostname == short name > >> c) dhcp : same as a) (fqdn) > >> > >> I can elaborate on that like this : > >> > >> a) as man said NM sets hostname "with the one provided via DHCP", which > is > >> first the short one (step1) then as a static profile is activated, it > falls > >> back to "hostname from the reverse lookup of the IP address" (which DNS > >> resolves in the fqdn) > > > > Right. > > >> b) : NM just don't play with the transient name and sets a static > hostname > >> coming from /etc/sysconfig/network > > > > NM sets the transient host name. It doesn't know about > > /etc/sysconfig/network. The hostname is determined in this way: > > But man says "none: NetworkManager will not manage the transient hostname > and will never set it." > Makes me wonder what exactly is the transient hostname. It's the kernel hostname, the one used among other things in the journal. > Besides, trace for 'none' confirms hostname is "unmanaged" > > So where does the short hostname I see in this case b) come from if not dhcp > (none) neither the sysconfig/network file ? Good question. It is not NM that sets it. > > https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/blob/1.20.0/src/nm-policy.c#L744 > > ok. But what does exactly "set outside of NetworkManager" mean ? > > > > No, it only takes the short hostname from DHCP. > > ok, makes sens as this is what's sent > > > > I don't know why it is setting the FQDN in your case. Could you please > > put level=trace in the [logging] section of > > /etc/NetworkManager/NetworkManager.conf, disabled journald > > ratelimiting, reproduce the issue and attach the journal log of a boot > > with hostname-mode=dhcp? > > Please find the 3 traces here: > > http://dl.pasteur.fr/fop/P3H6bSGV/NM-hostname-mode.tar.gz > > So basically, I still don't understand the 2 following cases > > - none (end up with short name) : if dhcp, NM seems to still manage the > hostname despite none In the 'none' log, the FQDN is set before NM starts. Around 14:53:41 someone adds a new connection and activates it, disconnecting the previous DHCP connection. At the same time the kernel hostname is changed externally to NM. I can't say who does this. > > - dhcp (end up with fqdn). In this case the short hostname got via DHCP is set by NM at 15:05:49. But later, somebody adds and activates a new connection 'xcat-enp33s0f0' with static addresses and so the DHCP hostname is removed, restoring the initial one. Beniamino _______________________________________________ networkmanager-list mailing list networkmanager-list@gnome.org https://mail.gnome.org/mailman/listinfo/networkmanager-list
