I have fresh installed Fedora 35 desktop on a NUC11pahi7, using fedora raid1. Initially all running as expected.
After doing a few dnf updates and re-booting each time (over several days), which did not generate any errors, I re-booted at one point (after an update) and got an error message when it was booting up, after bootloader while it was booting fedora.
During this reboot I got the error "Failed to start Load Kernel Modules" on the screen briefly, but the reboot completed successfully into the KDE x-11 plasma GUI. Everything seems to work.
From the Journal I found the message " Failed to insert module 'nf_conntrack_pptp': Invalid argument".

I have searched for related issues in the forum and found 4, but the issues were different from mine, and I could not corelate to my boot error.

Below I have pasted Various system info, command output and the relevant journal excerpt.

I am not experienced enough to understand what the journal log is telling me. There are references to files and directories in the log, which I have looked at, but I cannot find anything that looks wrong, but I do not know what I am looking for. This has been persistent through many subsequent dnf updates, including 3-4 new kernels. If anyone can point me to a next step in chasing the error, or any suggestions, I would appreciate it.

System info:
Boot- single boot EFI system (raid1 on boot partition)
uname -a = Linux fed-lf 5.16.16-200.fc35.x86_64 #1 SMP PREEMPT Sat Mar 19 13:52:41 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

some command output:
$systemctl --failed
UNIT LOAD ACTIVE SUB DESCRIPTION
0 loaded units listed.

$ systemctl status systemd-modules-load
● systemd-modules-load.service - Load Kernel Modules
Loaded: loaded (/usr/lib/systemd/system/systemd-modules-
load.service; static)
Active: active (exited) since Mon 2022-03-28 19:55:21 EDT; 1h
4min ago
Docs: man:systemd-modules-load.service(8)
man:modules-load.d(5)
Process: 843 ExecStart=/usr/lib/systemd/systemd-modules-load
(code=exited, status=0/SUC>
Main PID: 843 (code=exited, status=0/SUCCESS)
CPU: 8ms
Mar 28 19:55:21 fed-lf systemd-modules-load[843]: Module 'msr'
is built in
Mar 28 19:55:21 fed-lf systemd-modules-load[843]: Inserted
module 'nf_conntrack_pptp'
Mar 28 19:55:21 fed-lf systemd[1]: Finished Load Kernel
Modules.

$ systemctl status nf_conntrack_pptp
Unit nf_conntrack_pptp.service could not be found.

$ lsmod (output shortened)
thunderbolt 327680 0
igen6_edac 24576 0
acpi_tad 16384 0
acpi_pad 184320 0
nf_conntrack_pptp 20480 0 (seems to be loaded)
zram 28672 2
ip_tables 36864 0
hid_logitech_hidpp 49152 0

excerpt from Journal:
The job identifier is 39.
Mar 25 11:39:25 fed-lf kernel: audit: type=1130 audit(1648222765.971:4): pid=1 uid=0 auid=4294967295 ses=4294967295 subj=kernel msg='unit=systemd-vconsole-setup comm="systemd" exe="/usr/lib/systemd/systemd" hostname=>
Mar 25 11:39:25 fed-lf systemd-modules-load[276]: sh: line 1: /sbin/sysctl: No such file or directory
Mar 25 11:39:25 fed-lf systemd-modules-load[268]: Error running install command '/sbin/modprobe --ignore-install nf_conntrack && /sbin/sysctl --quiet --pattern 'net[.]netfilter[.]nf_conntrack.*' --system' for module>
Mar 25 11:39:25 fed-lf systemd-modules-load[268]: Failed to insert module 'nf_conntrack_pptp': Invalid argument
Mar 25 11:39:25 fed-lf systemd[1]: systemd-modules-load.service: Main process exited, code=exited, status=1/FAILURE
░░ Subject: Unit process exited
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailma.../systemd-devel
░░
░░ An ExecStart= process belonging to unit systemd-modules-load.service has exited.
░░
░░ The process' exit code is 'exited' and its exit status is 1.
Mar 25 11:39:25 fed-lf systemd[1]: systemd-modules-load.service: Failed with result 'exit-code'.
░░ Subject: Unit failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailma.../systemd-devel
░░
░░ The unit systemd-modules-load.service has entered the 'failed' state with result 'exit-code'.
Mar 25 11:39:25 fed-lf systemd[1]: Failed to start Load Kernel Modules.
░░ Subject: A start job for unit systemd-modules-load.service has failed
░░ Defined-By: systemd
░░ Support: https://lists.freedesktop.org/mailma.../systemd-devel
░░
░░ A start job for unit systemd-modules-load.service has finished with a failure.
░░
░░ The job identifier is 23 and the job result is failed.

The error you've highlighted in red is referring to the command on the previous line, i.e:
I'm not sure if that's one or two errors (i.e. /sbin/sysctl not existing (or having incorrect permissions) and/or an invalid argument to modprobe), but either way if this isn't something you configured yourself, then maybe it's a Fedora bug.

1 members found this post helpful.

Thanks so much for the info.
The file /sbin/sysctl does exist, and its permissions are 755 root root system_ubject_r:bin_t:s0, which matches the same file on a fedora 33 server I have access to.

I did not config any of this, it is just like it was installed. I think you may be right about it being a fedora bug. I am going to forget it for now. The system is working properly in every way that I can tell. ( It is just annoying to have errors show up when booting, but no big deal).

I appreciate the link, and I will file a bug report.

I do have 2 questions about the journal output:

1) Does "invalid argument" refer to the options listed after "/sbin/modprobe" ? That is, "--ignore-install nf_conntrack && /sbin/sysctl --quiet --pattern 'net[.]netfilter[.]nf_conntrack.*' --system"

2) In the verbage "sh: line 1: /sbin/sysctl:" what does the "sh: line 1" mean? Is "sh" referring to a shell script, and is there a place where I can look at that script "line 1"? I tried viewing sysctl, then realized it is object code.

Thanks again for the reply, I appreciate it.

Well the "&&" separates two commands (and thus two sets of options), with the second being conditional on the first, but that was my initial assumption.

However, all the arguments appear valid (at least based on Debian's man pages - I assume they're standard and Fedora's doesn't differ), and on closer look I'm wondering if the invalid argument might be referring to something inside one of the config files it is loading (as per --system).

One thing you can try is to run this and see if it complains:
Note the added "--dry-run" and "--verbose".

There's no dry-run option for sysctl, but I guess you could grep the config files that the --system option refers to and see if any match nf_conntrack, and then try to validate them.


sh is almost certainly the shell executable, i.e. "/bin/sh" (you can use "which sh" and "file /bin/sh" to confirm). This might be executabling a shell script, but it also might just be executing a shell command (via "sh -c 'command'").

I guess either way "systemd-modules-load.service" would be the place to start looking, and there's a man page for that which refers to modules-load.d which lists some directories containing conf files that might be worth inspecting.

1 members found this post helpful.

Thanks so much for the additional info. It is very helpful to my understanding what is happening.
I will try the suggestions you listed.

Thanks again.

After a lot of chasing through the config files, and some internet searches on strings in the conf files, I discovered:

For the "--system" option:
/etc/sysctl.conf contains the string "net.netfilter.nf_conntrack_helper=1
Apparently the "helper" is something to assist the firewall security when using pptp, because of issues with the pptp protocol security. The "1" activates the helper.

For the "modules-load.d"
/usr/lib/modules-load.d/pptpd.conf contains string "nf_conntrack_pptp" (Module that generated the "failed insertion" message).

So, I think what is happening is this:
The first part of the command:
"/sbin/modprobe --ignore-install nf_conntrack"
is saying ignore "install" in conf files, and load nf_conntrack_pptp (per "/usr/lib/modules-load.d/pptpd.conf").

The 2nd part of the command:
"/sbin/sysctl --quiet --pattern 'net[.]netfilter[.]nf_conntrack.*' --system"

is trying to load the pptp helper described above from the "--system" option.

I believe the error is coming from the /sbin/sysctl (pptp helper) command because the module nf_conntrack_pptp is correctly loaded after boot completes.

I cannot yet explain the error, but something in the 2nd part of the command looks strange to me. It seems the part of the command string " 'net[.]netfilter[.]nf_conntrack.*' ", which is a "pattern" should not have a "." after "conntrack", but just the "*". In the modules config file (above) the conf string reads: "nf_conntrack_pptp", and does not contain a ".". So, perhaps the command cannot find a suitable match to the "pattern", and errors out.

A lot of guess work, which is probably not all on target, but I think I know more now because of your suggestions than I did before. I appreciate the help very much.

Thanks so much for helping. I still plan to file a bug report.

It's a regex, where "." means "any character (except newline)" and "*" applies to the previous item and means "as many as possible, but zero needed" - in other words, ".*" in a regex pattern is equivalent to just "*" in a glob pattern.

In this example, the "[.]" part is a way of escaping to match a literal ".", so the pattern is simply saying "everything that starts with 'net.netfilter.nf_conntrack'"

1 members found this post helpful.

Perfect. That was the info I needed. I should have recognized that it was regex! I used it so much setting up fail2ban.

I appreciate the clarification.

You've been most helpful, and I appreciate your time.