You can inspect the certificates on each node to ensure that the names you added are present in the final output.
To inspect a certificate, execute the following command:
openssl x509 -in PATH_TO_CERT -ext subjectAltName -noout
Where PATH_TO_CERT is the certificate that you want to verify.
This command returns output similar to the following:
openssl x509 -in local_cert.pem -ext subjectAltName -noout X509v3 Subject Alternative Name: DNS:localhost, DNS:ipv4-localhost, DNS:ipv6-localhost, DNS:cli.dc-1.consul, DNS:client.dc-1.consul, DNS:server.dc-1.consul, DNS:prc-test-0-1337.edge-continious-integration.us-west-1a.google.com, IP Address:0.0.0.0, IP Address:127.0.0.1, IP Address:0:0:0:0:0:0:0:1, IP Address:10.126.0.117
The list of names and IP addresses should match those that you added in Step 2: Create the local signature config file.