Request for a certficate with multiple DNS names

We can secure a larger number of domains with only one certificate.

On the basis of this concept I installed single certificate on more then one websites.

To request a certificate which includes more than one FQDN (fully qualified domain name), We need to create a specially formatted CSR with more than one commonName (CN) in its subject.

Below are the steps to create and sign such certificate.

Step 1) Create a private key for requesting a certificate

[root@host2 load]# openssl genrsa -out www.domain.tld.key 2048

Step 2) Generate csr for multiple domains.

[root@host2 load]#openssl req -new -key  www.domain.tld.key -subj "/C=IE/O=inst_name/CN=first_fqdn/CN=second_fqdn/CN=third_fqdn"  -out www.domain.tld.csr

Step 3) As a CA Sign csr to certificate

[root@host2 load]# openssl ca -in www.domain.tld.csr -out www.domain.tld.crt