Chapter 1. Preparing to install on OpenStack

Procedure

1. Save the following script to your machine:

   #!/usr/bin/env bash
   
   set -Eeuo pipefail
   
   declare catalog san
   catalog="$(mktemp)"
   san="$(mktemp)"
   readonly catalog san
   
   declare invalid=0
   
   openstack catalog list --format json --column Name --column Endpoints \
   	| jq -r '.[] | .Name as $name | .Endpoints[] | select(.interface=="public") | [$name, .interface, .url] | join(" ")' \
   	| sort \
   	> "$catalog"
   
   while read -r name interface url; do
   	# Ignore HTTP
   	if [[ ${url#"http://"} != "$url" ]]; then
   		continue
   	fi
   
   	# Remove the schema from the URL
   	noschema=${url#"https://"}
   
   	# If the schema was not HTTPS, error
   	if [[ "$noschema" == "$url" ]]; then
   		echo "ERROR (unknown schema): $name $interface $url"
   		exit 2
   	fi
   
   	# Remove the path and only keep host and port
   	noschema="${noschema%%/*}"
   	host="${noschema%%:*}"
   	port="${noschema##*:}"
   
   	# Add the port if was implicit
   	if [[ "$port" == "$host" ]]; then
   		port='443'
   	fi
   
   	# Get the SAN fields
   	openssl s_client -showcerts -servername "$host" -connect "$host:$port" </dev/null 2>/dev/null \
   		| openssl x509 -noout -ext subjectAltName \
   		> "$san"
   
   	# openssl returns the empty string if no SAN is found.
   	# If a SAN is found, openssl is expected to return something like:
   	#
   	#    X509v3 Subject Alternative Name:
   	#        DNS:standalone, DNS:osp1, IP Address:192.168.2.1, IP Address:10.254.1.2
   	if [[ "$(grep -c "Subject Alternative Name" "$san" || true)" -gt 0 ]]; then
   		echo "PASS: $name $interface $url"
   	else
   		invalid=$((invalid+1))
   		echo "INVALID: $name $interface $url"
   	fi
   done < "$catalog"
   
   # clean up temporary files
   rm "$catalog" "$san"
   
   if [[ $invalid -gt 0 ]]; then
   	echo "${invalid} legacy certificates were detected. Update your certificates to include a SAN field."
   	exit 1
   else
   	echo "All HTTPS certificates for this cloud are valid."
   fi

2. Run the script.

3. Replace any certificates that the script reports as INVALID with certificates that contain SAN fields.

   Important

   You must replace all legacy HTTPS certificates before you install OpenShift Container Platform 4.10 or update a cluster to that version. Legacy certificates will be rejected with the following message:

   x509: certificate relies on legacy Common Name field, use SANs instead