Differences

This shows you the differences between two versions of the page.

--- lab:stack_-_discover_and_add_to_inventory [2023/04/30 01:15] – added lldp back in user
+++ lab:stack_-_discover_and_add_to_inventory [2023/05/01 19:43] (current) – updated user
@@ Line 1: / Line 1: @@
-====== Stack - Discover NUCs and Add to Inventory ======
-Now that you have your [[Stack of NUCs]] all built, updated, and connected to the wireless network, it is time to set them all up in the Ansible inventory so we can start doing things with them.
-Purpose:
-  * Discover local hosts that the Ansible control node can access
-  * Add these hosts to our inventory
-====== Step 1 - Power on All NUCs ======
-Power on all the NUCs. WiFi connectivity should make all visible to [[Stack - NUC 2|NUC 2]], the Ansible control node.
-====== Step 2 - Discover and Add to Inventory ======
-Run the following discovery script from the Ansible control node ([[Stack - NUC 2|NUC 2]]), and add the IP address to the inventory file ('hosts'). Copy the file to ''/home/ansible/my-project/discover.sh''
-<file bash discover.sh>
-if [ "$#" -ne 1 ]
-then
-  echo "Usage: $0 filename.txt"
-  echo "results will be appended to this file"
-  exit 1
-fi
-OUTPUT=$1
-[[ ! -z "$OUTPUT" ]] && touch $OUTPUT || exit
-IPs=$(sudo arp-scan --localnet --numeric --quiet --ignoredups | grep -E '([a-f0-9]{2}:){5}[a-f0-9]{2}' | awk '{print $1}')
-for i in ${IPs}; do
-  # set up SSH managment keys
-  ssh-keygen -q -R $i && ssh-keyscan -H $i >> ~/.ssh/known_hosts
-  # identify hosts ansible can access
-  ssh -q -o PasswordAuthentication=No $i "hostname -I" && echo $i && echo $i >> $OUTPUT
-done
-</file>
-Next, run the file: ''bash discover.sh hosts''
-This will find all the live hosts on the network, tried to SSH to all of them, added keys to the known_files file, and adding IP addresses of the Ansible worker notes to the "hosts" file.
-====== Step 3 - Identify Nodes That Weren't Discovered ======
-This is a quick and easy way to determine which ones weren't discovered: power off the ones that are working. Any of the NUCs still powered on has now been discovered.
-''ansible -i hosts all -a "poweroff"''
-Pull these NUCs for re-imaging/investigation. Next, power the "good" NUCs back on.
-You now have a working Ansible environment! Continue to our First Ansible playbook with [[stack_-_ansible_-_update|Ansible Update]].
-====== Optional ======
-===== Discover Using nmap scan =====
-You can discover ssh servers using nmap.
-  - Install nmap
-    * ''sudo apt install nmap -y''
-  - Run the following scan, replacing the network 192.168.1.0/24 with your Lab network
-    * ''nmap -p 22 --open -sV 192.168.1.0/24''
-  - You can see that all the NUCs you installed have the same OpenSSH version. Add these IP addresses to the ''hosts'' file under ''[nodes]''
-    * You will still need to add the hosts to the known hosts file
-===== Using lldp =====
-Another way to discover the NUCs on the network quickly and easily is to use lldp.
-NOTE: lldp is a standards-based neighbor discovery protocol similar to Cisco CDP. It works fine over wired network connections. However, some wireless routers drop lldp by default, so I have not included this in the lab.
-To use lldp in a wired lab
-  * add the ''lldpd'' to the list of packets to install using ''apt''
-  * install on NUC 1 using ''sudo apt install lldpd''
-  * from NUC 1 run ''lldpcli show neighbors''