85 lines
1.8 KiB
ReStructuredText
85 lines
1.8 KiB
ReStructuredText
Scan
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=====
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Description
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-----------
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Runs cdist as a daemon that discover/watch on hosts and reconfigure them
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periodically. It is especially useful in netboot-based environment where hosts
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boot unconfigured, and to ensure your infrastructure stays in sync with your
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configuration.
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This feature is still consider to be in **beta** stage, and only operate on
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IPv6 (including link-local).
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Usage (Examples)
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----------------
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Discover hosts on local network and configure those whose name is resolved by
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the name mapper script.
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.. code-block:: sh
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$ cdist scan --beta --interface eth0 \
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--mode scan --name-mapper path/to/script \
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--mode trigger --mode config
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List known hosts and exit.
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.. code-block:: sh
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$ cdist scan --beta --list --name-mapper path/to/script
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Please refer to `cdist(1)` for a detailed list of parameters.
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Modes
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-----
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The scanner has 3 modes that can be independently toggled. If the `--mode`
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parameter is not specified, only `tigger` and `scan` are enabled (= hosts are
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not configured).
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trigger
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Send ICMPv6 requests to specific hosts or broadcast over IPv6 link-local to
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trigger detection by the `scan` module.
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scan
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Watch for incoming ICMPv6 replies and optionally configure detected hosts.
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config
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Enable configuration of hosts detected by `scan`.
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Name Mapper Script
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------------------
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The name mapper script takes an IPv6 address as first argument and writes the
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resolved name to stdout - if any. The script must be executable.
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Simplest script:
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.. code-block:: sh
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#!/bin/sh
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case "$1" in
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"fe80::20d:b9ff:fe57:3524")
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printf "my-host-01"
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;;
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"fe80::7603:bdff:fe05:89bb")
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printf "my-host-02"
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;;
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esac
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Resolving name from `PTR` DNS record:
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.. code-block:: sh
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#!/bin/sh
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for cmd in dig sed; do
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if ! command -v $cmd > /dev/null; then
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exit 1
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fi
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done
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dig +short -x "$1" | sed -e 's/.$//'
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