sysconfig-network-configuration: Disable Auto Config Ethernet Devices

Disable automatic configuration on ethernet devices (DHCP/SLAAT) with no other matching connections Update modules/ROOT/pages/sysconfig-network-configuration.adoc Co-authored-by: Dusty Mabe <[email protected]> Update modules/ROOT/pages/sysconfig-network-configuration.adoc Co-authored-by: Dusty Mabe <[email protected]> Update modules/ROOT/pages/sysconfig-network-configuration.adoc Co-authored-by: Dusty Mabe <[email protected]> Update modules/ROOT/pages/sysconfig-network-configuration.adoc Co-authored-by: Dusty Mabe <[email protected]> provisioning/exoscale: Add note/warning about CLI compression Recommend users to use v1.54.0 and above and to never use the `--cloud-init-compress` argument. Closes coreos/fedora-coreos-tracker#1160 Add page for enabling kdump through ignition (coreos#388) sysconfig-network-configuration: Improve readability and look Improve readability and look of sysconfig-network Final commit
mohelt · May 9, 2022 · 6246269 · 6246269
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diff --git a/modules/ROOT/pages/debugging-kernel-crashes.adoc b/modules/ROOT/pages/debugging-kernel-crashes.adoc
@@ -1,15 +1,36 @@
 = Debugging kernel crashes using kdump
 
-. Memory must be reserved for the crash kernel during booting of the first kernel. `crashkernel=auto` is likely insufficient memory on Fedora CoreOS. It is recommended to start testing with 300M. Kernel arguments can be provided like this:
+== Introduction
+kdump is a service that creates crash dumps when there is a kernel crash. It uses kexec to boot into a secondary kernel (known as a capture kernel), then exports the contents of the kernel's memory (known as a crash dump or vmcore) to the filesystem. The contents of vmcore can then be analyzed to root cause the kernel crash.
+
+Configuring kdump requires setting the `crashkernel` kernel argument and enabling the kdump systemd service. Memory must be reserved for the crash kernel during booting of the first kernel. `crashkernel=auto` generally doesn't reserve enough memory on Fedora CoreOS, so it is recommended to specify `crashkernel=300M`. 
+
+By default, the vmcore will be saved in `/var/crash`. It is also possible to write the dump to some other location on the local system or to send it over the network by editing `/etc/kdump.conf`. For additional information, see https://www.mankier.com/5/kdump.conf[`kdump.conf(5)`] and the comments in `/etc/kdump.conf` and `/etc/sysconfig/kdump`.
+
+== Configuring kdump via Ignition
+.Example kdump configuration
+[source,yaml]
+----
+variant: fcos
+version: 1.4.0
+kernel_arguments:
+  should_exist:
+  - 'crashkernel=300M'
+systemd:
+  units:
+  - name: kdump.service
+    enabled: true
+----
+
+== Configuring kdump after initial provision
+. Set the crashkernel kernel argument
 +
 [source, bash]
 ----
 sudo rpm-ostree kargs --append='crashkernel=300M'
 ----
 xref:kernel-args.adoc[More information] on how to modify kargs via `rpm-ostree`.
 
-. By default, the path in which the vmcore will be saved is `/var/crash`. It is also possible to write the dump over the network or to some other location on the local system by editing `/etc/kdump.conf`. For additional information, see https://www.mankier.com/5/kdump.conf[`kdump.conf(5)`] and the comments in `/etc/kdump.conf` and `/etc/sysconfig/kdump`.
-
 . Enable the kdump systemd service.
 +
 [source, bash]

diff --git a/modules/ROOT/pages/provisioning-exoscale.adoc b/modules/ROOT/pages/provisioning-exoscale.adoc
@@ -52,6 +52,10 @@ You can then view the template using `exo compute instance-template show --visib
 
 You can provision a FCOS instance using the Exoscale https://portal.exoscale.com/compute/instances/add[Web Portal] or via the https://community.exoscale.com/documentation/tools/exoscale-command-line-interface/[Exoscale CLI].
 
+NOTE: You will need to use at least version https://github.com/exoscale/cli/releases/tag/v1.54.0[v1.54.0] of the Exoscale CLI.
+
+WARNING: Do not use the `--cloud-init-compress` argument to the CLI.  It causes the Ignition config to be passed compressed to the instance and https://github.com/coreos/fedora-coreos-tracker/issues/1160[Ignition doesn't tolerate that].
+
 .Launching a new instance with Exoscale CLI
 [source, bash]
 ----

diff --git a/modules/ROOT/pages/sysconfig-network-configuration.adoc b/modules/ROOT/pages/sysconfig-network-configuration.adoc
@@ -4,7 +4,7 @@
 
 === Background
 
-By default, Fedora CoreOS (FCOS) will attempt DHCP on every interface with a cable plugged in. However, if you need to use static addressing or more complex networking (vlans, bonds, bridges, teams, etc..), you can do so in a number of ways which are summarized below. Regardless of the way you choose to configure networking it all ends up as configuration for NetworkManager, which takes the form of NetworkManager keyfiles. More information on the keyfile format can be found https://developer.gnome.org/NetworkManager/stable/nm-settings-keyfile.html[here]. More information on the subsection options for keyfiles can be found https://developer.gnome.org/NetworkManager/stable/ref-settings.html[here].
+Unless xref:#_disabling_automatic_configuration_of_ethernet_devices[otherwise configured], Fedora CoreOS (FCOS) will attempt DHCP on every interface with a cable plugged in. However, if you need to use static addressing or more complex networking (vlans, bonds, bridges, teams, etc..), you can do so in a number of ways which are summarized below. Regardless of the way you choose to configure networking it all ends up as configuration for NetworkManager, which takes the form of NetworkManager keyfiles. More information on the keyfile format can be found https://developer.gnome.org/NetworkManager/stable/nm-settings-keyfile.html[here]. More information on the subsection options for keyfiles can be found https://developer.gnome.org/NetworkManager/stable/ref-settings.html[here].
 
 === Configuration Options
 
@@ -890,3 +890,26 @@ storage:
           master=bond0
           slave-type=bond
 ----
+=== Disabling Automatic Configuration of Ethernet Devices
+
+By default, FCOS will attempt to autoconfigure (DHCP/SLAAC) on every interface with a cable plugged in. In some network environments this may not be desirable. It's possible to change this behavior of NetworkManager with a configuration file dropin:
+
+
+.Disable NetworkManager autoconfiguration of ethernet devices
+[source, yaml]
+----
+variant: fcos
+version: 1.4.0
+storage:
+  files:
+     - path: /etc/NetworkManager/conf.d/noauto.conf
+      mode: 0644 
+      contents: 
+        inline: |
+          [main]
+          # Do not do automatic (DHCP/SLAAC) configuration on ethernet devices
+          # with no other matching connections.
+          no-auto-default=* 
+----
+
+ WARNING: If NetworkManager autoconfiguration of ethernet devices is disabled and no other network configuration is provided the system will boot without network access.