Re: [gentoo-user] Spurious error messages at boot up from the new dhcpcd

[Alan Mackenzie <acm@muc.de>]

Hello, Michael.

On Tue, Aug 22, 2023 at 12:29:38 +0100, Michael wrote:
> On Tuesday, 22 August 2023 10:56:52 BST Alan Mackenzie wrote:
> > Hello, gentoo.

> > With the new dhcpcd-10.0.2 (previous version being ?9.5.1) I get spurious
> > error messages on boot up.  In particular, I see this:

> >  * Starting DHCP Client Daemon ...
> >  * [ ok ] * Bringing up interface enp38s0
> >  *   Caching network module dependencies
> >  *   config_enp38s0 not specified; defaulting to DHCP
> >  *   dhcp ...
> >  *     The dhcpcd version is too old. Please upgrade.
> >  *     [ !! ] * ERROR: net.enp38s0 failed to start

> > ..  However, after ~1 hour searching for the problem, I just tried using
> > enp38s0 to ssh onto my ISP, and it worked.  In /var/log/messages, I see
> > the following:

> > Aug 22 09:24:20 ACM dhcpcd[2435]: dhcpcd-10.0.2 starting
> > Aug 22 09:24:20 ACM dhcpcd[2437]: dev: loaded udev
> > Aug 22 09:24:20 ACM dhcpcd[2437]: DUID
> > 00:01:00:01:20:97:45:37:60:45:cb:9c:5b:d6 Aug 22 09:24:20 ACM dhcpcd[2437]:
> > enp38s0: waiting for carrier
> > Aug 22 09:24:22 ACM kernel: igb 0000:26:00.0 enp38s0: igb: enp38s0 NIC Link
> > is Up 1000 Mbps Full Duplex, Flow Control: RX/TX Aug 22 09:24:23 ACM
> > dhcpcd[2437]: enp38s0: carrier acquired
> > Aug 22 09:24:23 ACM kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp38s0: link
> > becomes ready Aug 22 09:24:23 ACM dhcpcd[2437]: enp38s0: IAID cb:9c:5b:d6
> > Aug 22 09:24:24 ACM dhcpcd[2437]: enp38s0: rebinding lease of 192.168.178.86
> > Aug 22 09:24:24 ACM dhcpcd[2437]: enp38s0: probing address
> > 192.168.178.86/24 Aug 22 09:24:28 ACM dhcpcd[2437]: enp38s0: leased
> > 192.168.178.86 for 864000 seconds Aug 22 09:24:28 ACM dhcpcd[2437]:
> > enp38s0: adding route to 192.168.178.0/24 Aug 22 09:24:28 ACM dhcpcd[2437]:
> > enp38s0: adding default route via 192.168.178.1 Aug 22 09:24:29 ACM
> > /etc/init.d/net.enp38s0[2686]: config_enp38s0 not specified; defaulting to
> > DHCP

> I don't know what your network configuration requirements may be, but if you 
> have not specified a manual configuration for your enp38s0 interface, then you 
> probably do not need the netifrc service enabled.  You can remove net.enp38s0 
> service from the default runlevel and reboot, with an eye on the log messages.

I am running a simple workstation, connected to a consumer-grade router
by an ethernet cable.  I didn't (and don't) have a specific configuration
for enp38s0.  I did

    $ rc-update del net.enp38s0 default

and rebooted.  The machine came up without error messages, indeed with
fewer messages than it used to.  On tty1, I now see just:

INIT: Entering runlevel: 3
 * Checking your configfile (/etc/syslog-ng/syslog-ng.conf) ...
 * [ ok ] * Starting syslog-ng ...
 * [ ok ] * Starting DHCP Client Daemon ...
 * [ ok ] * Setting clock via the NTP client 'ntpdate' ...
 * [ ok ] * Starting cronie ...
 * [ ok ] * Starting dbus ...
 * [ ok ] * Starting cupsd ...
 * [ ok ] * Starting gpm ...
 * [ ok ] * Mounting network filesystems ...
 * [ ok ] * Starting local ...

, and in /var/log/message I see:

Aug 22 12:36:56 ACM dhcpcd[2435]: dhcpcd-10.0.2 starting
Aug 22 12:36:56 ACM dhcpcd[2437]: dev: loaded udev
Aug 22 12:36:56 ACM dhcpcd[2437]: DUID 00:01:00:01:20:97:45:37:60:45:cb:9c:5b:d6
Aug 22 12:36:56 ACM dhcpcd[2437]: enp38s0: waiting for carrier
Aug 22 12:36:58 ACM kernel: igb 0000:26:00.0 enp38s0: igb: enp38s0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX/TX
Aug 22 12:36:59 ACM dhcpcd[2437]: enp38s0: carrier acquired
Aug 22 12:36:59 ACM kernel: IPv6: ADDRCONF(NETDEV_CHANGE): enp38s0: link becomes ready
Aug 22 12:36:59 ACM dhcpcd[2437]: enp38s0: IAID cb:9c:5b:d6
Aug 22 12:37:00 ACM dhcpcd[2437]: enp38s0: rebinding lease of 192.168.178.86
Aug 22 12:37:00 ACM dhcpcd[2437]: enp38s0: probing address 192.168.178.86/24
Aug 22 12:37:05 ACM dhcpcd[2437]: enp38s0: leased 192.168.178.86 for 864000 seconds
Aug 22 12:37:05 ACM dhcpcd[2437]: enp38s0: adding route to 192.168.178.0/24
Aug 22 12:37:05 ACM dhcpcd[2437]: enp38s0: adding default route via 192.168.178.1

..

> > Aug 22 09:24:29 ACM /etc/init.d/net.enp38s0[2695]: The dhcpcd version
> > is too old. Please upgrade.

> I'm running the same version like you and do not see this message, but this 
> does not explain why you get this printed out.

I don't understand what I just did, by deleting net.enp38s0, though it
appeared to have fixed the problem.  That worries me.  Could you possibly
explain to me a bit more what that removal did?  Thanks!

> I expect you have the dhcpcd service enabled.  Does your NIC come up and 
> obtain an IP address via dhcpcd, if you remove dhcpcd from the default 
> runlevel?  Careful you do not lock yourself out, if this is a remote system 
> and no network comes up when you reboot.

On removing dhcpcd from default, the maching just has no network
connection on booting up.

> > Aug 22 09:24:29 ACM
> > /etc/init.d/net.enp38s0[2527]: ERROR: net.enp38s0 failed to start

> > ..

> > So it would appear that everything is working, but I still get error
> > messages.  The "dhcpcd version is too old" is particularly galling, given
> > that dhcpcd was updated yesterday.

> Unless you emerge the latest from trunk, 10.0.2 is shown as the latest stable 
> dhcpcd version:

> [I] net-misc/dhcpcd
>      Available versions:  
>             9.4.1	[debug +embedded ipv6 privsep +udev]
>             9.5.1	[debug +embedded ipv6 privsep +udev]
>        ~    10.0.1	[debug +embedded ipv6 privsep +udev]
>             10.0.2	[debug +embedded ipv6 privsep +udev]
>        **   9999      *l	[debug +embedded ipv6 privsep +udev]
>      Installed versions:  10.0.2(09:27:21 08/21/23)(embedded ipv6 udev -debug 
> -privsep)

Yes, I just emerged it yesterday.

So, the current state is my machine appears to be working, without error
messages on boot-up, but I don't understand why.

-- 
Alan Mackenzie (Nuremberg, Germany).