NetworkManager/man/nm-initrd-generator.xml

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  SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later

  nm-initrd-generator(8) manual page

  Copyright 2018 Red Hat, Inc.
-->

<refentry id='nm-initrd-generator'>

  <refentryinfo>
    <title>nm-initrd-generator</title>
    <author>NetworkManager developers</author>
  </refentryinfo>

  <refmeta>
    <refentrytitle>nm-initrd-generator</refentrytitle>
    <manvolnum>8</manvolnum>
    <refmiscinfo class="source">NetworkManager</refmiscinfo>
    <refmiscinfo class="manual">System Administration</refmiscinfo>
    <refmiscinfo class="version">&NM_VERSION;</refmiscinfo>
  </refmeta>

  <refnamediv>
    <refname>nm-initrd-generator</refname>
    <refpurpose>early boot NetworkManager configuration generator</refpurpose>
  </refnamediv>

  <refsynopsisdiv id='synopsis'>
    <cmdsynopsis>
      <command>nm-initrd-generator</command>
      <arg choice="opt" rep="repeat"><replaceable>OPTIONS</replaceable></arg>
      <arg choice="plain">--</arg>
      <arg choice="opt" rep="repeat"><replaceable>CMDLINE</replaceable></arg>
    </cmdsynopsis>
  </refsynopsisdiv>

  <refsect1 id='description'><title>Description</title>
    <para><command>nm-initrd-generator</command> scans the command line for options
    relevant to network configuration and creates configuration files for an early
    instance of NetworkManager run from the initial ramdisk during early boot.</para>
  </refsect1>

  <refsect1 id='options'><title>Options</title>
    <variablelist>
      <varlistentry>
        <term>
          <group choice='plain'>
            <arg choice='plain'><option>-c</option></arg>
            <arg choice='plain'><option>--connections-dir</option></arg>
          </group>
          <arg choice='plain'><replaceable>path</replaceable></arg>
        </term>

        <listitem>
          <para>Output connection directory.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <group choice='plain'>
            <arg choice='plain'><option>-p</option></arg>
            <arg choice='plain'><option>--persistent-connections-dir</option></arg>
          </group>
          <arg choice='plain'><replaceable>path</replaceable></arg>
        </term>

        <listitem>
          <para>Persistent connection directory. If it exists, rd.neednet will not
          cause a default connection to be generated in absence of other options.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <group choice='plain'>
            <arg choice='plain'><option>-i</option></arg>
            <arg choice='plain'><option>--initrd-data-dir</option></arg>
          </group>
          <arg choice='plain'><replaceable>path</replaceable></arg>
        </term>

        <listitem>
          <para>Output directory for initrd data (e.g. hostname).</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <group choice='plain'>
            <arg choice='plain'><option>-d</option></arg>
            <arg choice='plain'><option>--sysfs-dir</option></arg>
          </group>
          <arg choice='plain'><replaceable>path</replaceable></arg>
        </term>

        <listitem>
          <para>The sysfs mount point.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <group choice='plain'>
            <arg choice='plain'><option>-r</option></arg>
            <arg choice='plain'><option>--run-config-dir</option></arg>
          </group>
          <arg choice='plain'><replaceable>path</replaceable></arg>
        </term>

        <listitem>
          <para>Output directory for config files.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term>
          <group choice='plain'>
            <arg choice='plain'><option>-s</option></arg>
            <arg choice='plain'><option>--stdout</option></arg>
          </group>
        </term>

        <listitem>
          <para>Dump connections to standard output. Useful for debugging.</para>
        </listitem>
      </varlistentry>

      <varlistentry>
        <term><replaceable>CMDLINE</replaceable></term>

        <listitem>
          <para>The options that appear on the kernel command line. The following options are recognized:</para>

          <simplelist>
            <member><option>ip</option></member>
            <member><option>rd.route</option></member>
            <member><option>bridge</option></member>
            <member><option>bond</option></member>
            <member><option>team</option></member>
            <member><option>vlan</option></member>
            <member><option>ib.pkey</option></member>
            <member><option>bootdev</option></member>
            <member><option>nameserver</option></member>
            <member><option>net.ifnames</option></member>
            <member><option>rd.peerdns</option></member>
            <member><option>rd.iscsi.ibft</option></member>
            <member><option>rd.nvmf.nonbft</option></member>
            <member><option>rd.bootif</option></member>
            <member><option>rd.neednet</option></member>
            <member><option>rd.ethtool</option></member>
            <member><option>rd.net.dns</option></member>
            <member><option>rd.net.dns-backend</option></member>
            <member><option>rd.net.dns-resolve-mode</option></member>
            <member><option>rd.net.timeout.dhcp</option></member>
            <member><option>rd.net.dhcp.client-id</option></member>
            <member><option>rd.net.dhcp.retry</option></member>
            <member><option>rd.net.dhcp.vendor-class</option></member>
            <member><option>rd.net.dhcp.dscp</option></member>
            <member><option>rd.net.timeout.carrier</option></member>
            <member><option>rd.znet</option></member>
            <member><option>rd.znet_ifname</option></member>
            <member><option>BOOTIF</option></member>
          </simplelist>

          <para>Please consult the <citerefentry><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry>
          manual for the documentation of the precise format of the values supported.</para>
        </listitem>
      </varlistentry>
    </variablelist>
  </refsect1>

  <refsect1 id='differences_from_network_legacy'><title>Differences from the network-legacy dracut module</title>

    <para><command>nm-initrd-generator</command> generates a set of
    connections that are then configured by the NetworkManager
    instance running in the initrd. There are some differences in
    behavior compared to the network-legacy dracut module:</para>

    <itemizedlist>
      <listitem>
        <para>When an interface is configured with a static address
        and a gateway, the network-legacy module waits that the
        gateway responds to arping requests before proceeding, while
        NetworkManager doesn't.</para>
      </listitem>

      <listitem>
        <para>network-legacy configures interfaces one by one in the
        order in which they are announced by udev. If multiple
        interfaces specify a hostname (from command line or from
        DHCP), the one from the last interface activated wins. With
        NetworkManager, hostnames from command line have higher
        precedence over ones from DHCP, and the last that appears in
        the command line wins.</para>
      </listitem>

      <listitem>
        <para>NetworkManager supports the
        <option>ib.pkey</option>=<replaceable>PARENT</replaceable>.<replaceable>PKEY</replaceable>
        argument to set up an Infiniband partition on IPoIB parent
        device <replaceable>PARENT</replaceable> using the specified
        partition key <replaceable>PKEY</replaceable>. The partition
        key must be in hexadecimal notation without leading "0x", for
        example "ib.pkey=ib0.8004".
        </para>
      </listitem>

      <listitem>
        <para>NetworkManager supports the 
        <option>rd.ethtool</option>=<replaceable>INTERFACE</replaceable>:<replaceable>AUTONEG</replaceable>:<replaceable>SPEED</replaceable> 
        kernel command line option to set up ethtool NIC configuration parameters 
        <replaceable>AUTONEG</replaceable> and <replaceable>SPEED</replaceable>. 
        The <replaceable>INTERFACE</replaceable> being configured must be 
        specified, and the other parameters are optional and can be left blank. 
        When <replaceable>SPEED</replaceable> is set, duplex mode is 
        automatically set to 'full'. <replaceable>INTERFACE</replaceable> 
        accepts string values, <replaceable>AUTONEG</replaceable> accepts 
        boolean values (true and false / on or off / 0 or 1), and 
        <replaceable>SPEED</replaceable> accepts positive integer values.
        </para>
      </listitem>

      <listitem>
        <para>NetworkManager supports the
        <option>rd.net.dns-backend</option>=<replaceable>VALUE</replaceable>
        kernel command line option to configure the DNS processing
        mode. See the description of the <literal>"dns"</literal> key in
        the <literal>"main section"</literal> paragraph of <link
        linkend='NetworkManager.conf'><citerefentry><refentrytitle>NetworkManager.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry></link>. For
        example: <literal>rd.net.dns-backend=systemd-resolved</literal>,
        <literal>rd.net.dns-backend=dnsconfd</literal>
        </para>
      </listitem>

      <listitem>
        <para>NetworkManager supports the
        <option>rd.net.dns</option>=<replaceable>SERVER</replaceable>
        kernel command line option to configure a global (non
        interface-specific) DNS server. The option can be specified
        multiple time to add more than one server. Each server can be
        specified as a plain IP or as an URI according to the
        description in the "global-dns-domains sections" paragraph of
        <link
        linkend='NetworkManager.conf'><citerefentry><refentrytitle>NetworkManager.conf</refentrytitle><manvolnum>5</manvolnum></citerefentry></link>. For
        example: <literal>rd.net.dns=2001:db8::1</literal>,
        <literal>rd.net.dns=dns+tls://192.0.2.0</literal>,
        <literal>rd.net.dns=dns+tls://[2001:db8::2]:5353#example.org</literal>.
        In addition, it supports configuring the <literal>"resolve-mode"</literal>
        key in the global DNS configuration via the
        <option>rd.net.dns-resolve-mode</option> command line option.
        </para>
      </listitem>

      <listitem>
        <para>NetworkManager supports the
        <option>rd.net.dhcp.dscp</option>={<replaceable>CS0</replaceable>|<replaceable>CS4</replaceable>|<replaceable>CS6</replaceable>}
        kernel command line option to set a specific DSCP (TOS) value
        in the IP header of DHCP messages.
        </para>
      </listitem>

      <listitem>
        <para>NetworkManager supports the
        <option>rd.net.dhcp.client-id</option>=<replaceable>interface</replaceable>:<replaceable>client-id</replaceable>
        kernel command line option to set a specific DHCPv4 client identifier
        for the given interface. The client-id can be specified either as a
        sequence of bytes in hexadecimal format separated by dashes, or as the
        character '@' followed by a non-empty string. When using the second
        format, NetworkManager prepends a zero byte to the given string,
        according to section 9.14 of RFC 2132. See the "ipv4.dhcp-client-id"
        section of <link
        linkend='nm-settings-nmcli'><citerefentry><refentrytitle>nm-settings-nmcli</refentrytitle><manvolnum>5</manvolnum></citerefentry></link>
        for more details. Examples:
        <literal>rd.net.dhcp.client-id=eth0:01-52-54-00-45-87-42</literal>,
        <literal>rd.net.dhcp.client-id=enp1s0:@example.com</literal>.
        </para>
      </listitem>

    </itemizedlist>
  </refsect1>

  <refsect1 id='exit_status'><title>Exit Status</title>
    <para><command>nm-initrd-generator</command> exits with status 0. It ignores unrecognized
    options and prints an error message if it encounters a malformed option.</para>
  </refsect1>

  <refsect1 id='see_also'><title>See Also</title>
    <para><link linkend='dracut.cmdline'><citerefentry><refentrytitle>dracut.cmdline</refentrytitle><manvolnum>7</manvolnum></citerefentry></link>,
    <link linkend='NetworkManager'><citerefentry><refentrytitle>NetworkManager</refentrytitle><manvolnum>8</manvolnum></citerefentry></link>,
    <link linkend='nm-settings-nmcli'><citerefentry><refentrytitle>nm-settings-nmcli</refentrytitle><manvolnum>5</manvolnum></citerefentry></link>.</para>
  </refsect1>
</refentry>