
There are numerous let’s encrypt automated instruments for azure however I additionally wished to see if I might use certbot in wsl to generate a wildcard certificates for the azure Friday web site after which add the ensuing certificates to azure app service.
Azure app service finally wants a particular format referred to as dot PFX that features the complete certificates path and all intermediates.
Per the docs, App Service personal certificates should meet the next necessities:
- Exported as a password-protected PFX file, encrypted utilizing triple DES.
- Accommodates personal key no less than 2048 bits lengthy
- Accommodates all intermediate certificates and the foundation certificates within the certificates chain.
If in case you have a PFX that does not meet all these necessities you’ll be able to have Home windows reencrypt the file.
I exploit WSL and certbot to create the cert, then I import/export in Home windows and add the ensuing PFX.
Inside WSL, set up certbot:
sudo apt replace
sudo apt set up python3 python3-venv libaugeas0
sudo python3 -m venv /decide/certbot/
sudo /decide/certbot/bin/pip set up --upgrade pip
sudo /decide/certbot/bin/pip set up certbot
Then I generate the cert. You may get a pleasant textual content UI from certbot and replace your DNS as a verification problem. Change this to verify it is two strains, and your domains and subdomains are right and your paths are right.
sudo certbot certonly --manual --preferred-challenges=dns --email YOUR@EMAIL.COM
--server https://acme-v02.api.letsencrypt.org/listing
--agree-tos --manual-public-ip-logging-ok -d "azurefriday.com" -d "*.azurefriday.com"
sudo openssl pkcs12 -export -out AzureFriday2023.pfx
-inkey /and many others/letsencrypt/reside/azurefriday.com/privkey.pem
-in /and many others/letsencrypt/reside/azurefriday.com/fullchain.pem
I then copy the ensuing file to my desktop (test your desktop path) so it is now within the Home windows world.
sudo cp AzureFriday2023.pfx /mnt/c/Customers/Scott/OneDrive/Desktop
Now from Home windows, import the PFX, be aware the thumbprint and export that cert.
Import-PfxCertificate -FilePath "AzureFriday2023.pfx" -CertStoreLocation Cert:LocalMachineMy
-Password (ConvertTo-SecureString -String 'PASSWORDHERE' -AsPlainText -Power) -ExportableExport-PfxCertificate -Cert Microsoft.PowerShell.SecurityCertificate::LocalMachineMy597THISISTHETHUMBNAILCF1157B8CEBB7CA1
-FilePath 'AzureFriday2023-fixed.pfx' -Password (ConvertTo-SecureString -String 'PASSWORDHERE' -AsPlainText -Power)
Then add the cert to the Certificates part of your App Service, beneath Carry Your Personal Cert.

Then beneath Customized Domains, click on Replace Binding and choose the brand new cert (with the most recent expiration date).
Subsequent step is to make this much more automated or choose a extra automated resolution however for now, I am going to fear about this in September and it solved my costly Wildcard Area subject.
About Scott
Scott Hanselman is a former professor, former Chief Architect in finance, now speaker, guide, father, diabetic, and Microsoft worker. He’s a failed stand-up comedian, a cornrower, and a ebook creator.