just something that came up while setting up a monitoring script using mailx, figured ill note it down here so i can get it to easily later when I need it 😀
Important prerequisites
You need to enable smtp basic Auth on Office 365 for the account used for authentication
Create an App password for the user account
nssdb folder must be available and readable by the user running the mailx command
Assuming all of the above prerequisite are $true we can proceed with the setup
Install mailx
RHEL/Alma linux
sudo dnf install mailx
NSSDB Folder
make sure the nssdb folder must be available and readable by the user running the mailx command
certutil -L -d /etc/pki/nssdb
The Output might be empty, but that’s ok; this is there if you need to add a locally signed cert or another CA cert manually, Microsoft Certs are trusted by default if you are on an up to date operating system with the local System-wide Trust Store
Append/prepend the following lines and Comment out or remove the same lines already defined on the existing config files
set smtp=smtp.office365.com
set smtp-auth-user=###[email protected]###
set smtp-auth-password=##Office365-App-password#
set nss-config-dir=/etc/pki/nssdb/
set ssl-verify=ignore
set smtp-use-starttls
set from="###[email protected]###"
This is the bare minimum needed other switches are located here – link
-v switch will print the verbos debug log to console
Connecting to 52.96.40.242:smtp . . . connected.
220 xxde10CA0031.outlook.office365.com Microsoft ESMTP MAIL Service ready at Sun, 6 Aug 2023 22:14:56 +0000
>>> EHLO vls-xxx.multicastbits.local
250-MN2PR10CA0031.outlook.office365.com Hello [167.206.57.122]
250-SIZE 157286400
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-STARTTLS
250-8BITMIME
250-BINARYMIME
250-CHUNKING
250 SMTPUTF8
>>> STARTTLS
220 2.0.0 SMTP server ready
>>> EHLO vls-xxx.multicastbits.local
250-xxde10CA0031.outlook.office365.com Hello [167.206.57.122]
250-SIZE 157286400
250-PIPELINING
250-DSN
250-ENHANCEDSTATUSCODES
250-AUTH LOGIN XOAUTH2
250-8BITMIME
250-BINARYMIME
250-CHUNKING
250 SMTPUTF8
>>> AUTH LOGIN
334 VXNlcm5hbWU6
>>> Zxxxxxxxxxxxc0BmdC1zeXMuY29t
334 UGsxxxxxmQ6
>>> c2Rxxxxxxxxxxducw==
235 2.7.0 Authentication successful
>>> MAIL FROM:<###[email protected]###>
250 2.1.0 Sender OK
>>> RCPT TO:<[email protected]>
250 2.1.5 Recipient OK
>>> DATA
354 Start mail input; end with <CRLF>.<CRLF>
>>> .
250 2.0.0 OK <[email protected]> [Hostname=Bsxsss744.namprd11.prod.outlook.com]
>>> QUIT
221 2.0.0 Service closing transmission channel
Now you can use this in your automation scripts or timers using the mailx command
#!/bin/bash
log_file="/etc/app/runtime.log"
recipient="[email protected]"
subject="Log file from /etc/app/runtime.log"
# Check if the log file exists
if [ ! -f "$log_file" ]; then
echo "Error: Log file not found: $log_file"
exit 1
fi
# Use mailx to send the log file as an attachment
echo "Sending log file..."
mailx -s "$subject" -a "$log_file" -r "[email protected]" "$recipient" < /dev/null
echo "Log file sent successfully."
The above commands change the file’s owner and group to root, then set the file permissions to 600, which means only the owner (root) has read and write permissions and other users have no access to the file.
Use Environment Variables: Avoid storing sensitive information like passwords directly in the mail.rc file, consider using environment variables for sensitive data and reference those variables in the configuration.
For example, in the mail.rc file, you can set:
set smtp-auth-password=$MY_EMAIL_PASSWORD
You can set the variable using another config file or store it in the Ansible vault during runtime or use something like Hashicorp.
Sure, I would just use Python or PowerShell core, but you will run into more locked-down environments like OCI-managed DB servers with only Mailx is preinstalled and the only tool you can use 🙁
the Fact that you are here means you are already in the same boat. Hope this helped… until next time
Let’s talk a little bit about this code and unpack this
Vagrant API version
Vagrant uses API versions for its configuration file, this is how it can stay backward compatible. So in every Vagrantfile we need to specify which version to use. The current one is version 2 which works with Vagrant 1.1 and up.
Provisioning the Ansible VM
This will
Provision the controller Ubuntu VM
Create a bridged network adapter
Set the host-name – LAB-Controller
Set the static IP – 172.17.10.120/24
Run the Shell script that installs Ansible using apt-get install (We will get to this below)
Lets start digging in…
Specifying the Controller VM Name, base box and hostname
Vagrant uses a base image to clone a virtual machine quickly. These base images are known as “boxes” in Vagrant, and specifying the box to use for your Vagrant environment is always the first step after creating a new Vagrantfile.
Define the shell script to customize the VM config and install the Ansible Package
Now this is where we define the provisioning shell script
this script installs Ansible and set the host file entries to make your life easier
In case you are wondering VLS stands for V=virtual,L – linux S – server.
I use this naming scheme for my VMs. Feel free to use anything you want; make sure it matches what you defined on the Vagrantfile under node.vm.hostname
We covered most of the code used above, the only difference here is we are using each method to create 3 VMs with the same template (I’m lazy and it’s more convenient)
This will create three Ubuntu VMs with the following Host-names and IP addresses, you should update these values to match you LAN, or use a private Adapter
vls-node1 – 172.17.10.121
vls-node2 – 172.17.10.122
vls-node1 – 172.17.10.123
So now that we are done with explaining the code, let’s run this
Building the Lab environment using Vagrant
Issue the following command to check your syntax
Vagrant status
Issue the following command to bring up the environment
Vagrant up
If you get this message Reboot in to UEFI and make sure virtualization is enabled
Intel – VT-D
AMD Ryzen – SVM
If everything is kumbaya you will see vagrant firing up the deployment
It will provision 4 VMs as we specified
Notice since we have the “vagrant-vbguest” plugin installed, it will reinstall the relevant guest tools along with the dependencies for the OS
==> vls-node3: Machine booted and ready!
[vls-node3] No Virtualbox Guest Additions installation found.
rmmod: ERROR: Module vboxsf is not currently loaded
rmmod: ERROR: Module vboxguest is not currently loaded
Reading package lists...
Building dependency tree...
Reading state information...
Package 'virtualbox-guest-x11' is not installed, so not removed
The following packages will be REMOVED:
virtualbox-guest-utils*
0 upgraded, 0 newly installed, 1 to remove and 0 not upgraded.
After this operation, 5799 kB disk space will be freed.
(Reading database ... 61617 files and directories currently installed.)
Removing virtualbox-guest-utils (6.0.14-dfsg-1) ...
Processing triggers for man-db (2.8.7-3) ...
(Reading database ... 61604 files and directories currently installed.)
Purging configuration files for virtualbox-guest-utils (6.0.14-dfsg-1) ...
Processing triggers for systemd (242-7ubuntu3.7) ...
Reading package lists...
Building dependency tree...
Reading state information...
linux-headers-5.3.0-51-generic is already the newest version (5.3.0-51.44).
linux-headers-5.3.0-51-generic set to manually installed.
Check the status
Vagrant status
Testing
Connecting via SSH to your VMs
vagrant ssh controller
“Controller” is the VMname we defined before not the hostname, You can find this by running Vagrant status on posh or your terminal
We are going to connect to our controller and check everything
Little bit more information on the networking side
Vagrant Adds two interfaces, for each VM
NIC 1 – Nat’d in to the host (control plane for Vagrant to manage the VMs)
NIC 2 – Bridged adapter we provisioned in the script with the IP Address
Default route is set via the Private(NAT’d) interface (you cant change it)
Netplan configs
Vagrant creates a custom netplan yaml for interface configs
I hope this helped someone. when I started with Vagrant a few years back it took me a few tries to figure out the system and the logic behind it, this will give you a basic understanding on how things are plugged together.
let me know in the comments if you see any issues or mistakes.