Openssl CSR with Multiple Host Names - SubjectAltNames

Create a temporary config file with the following details and name is as "req.conf"

**********************************
[ req ]
default_bits        = 2048
default_keyfile     = privkey.pem
distinguished_name  = req_distinguished_name
req_extensions     = req_ext # The extentions to add to the self signed cert

[ req_distinguished_name ]
countryName           = Country Name (2 letter code)
countryName_default   = US
stateOrProvinceName   = State or Province Name (full name)
stateOrProvinceName_default = Illinois
localityName          = Locality Name (eg, city)
localityName_default  = Chicago
organizationName          = Organization Name (eg, company)
organizationName_default  = Example, Co.
commonName            = Common Name (eg, YOUR name)
commonName_max        = 64

[ req_ext ]
subjectAltName          = @alt_names

[alt_names]
DNS.1   = <Name of the hostname that will be recognized by browser>
DNS.2   = <Name of the hostname that will be recognized by browser>
DNS.3   = <Name of the hostname that will be recognized by browser>
DNS.4   = <Name of the hostname that will be recognized by browser>




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The Private Key is created in the directory where the Openssl.exe is available.

Once the config file is ready. Run the following Open SSL Command:

openssl req -new -nodes -out myreq.csr -config req.conf



Now submit the CSR to CA for new certificate.

Source: http://langui.sh/2009/02/27/creating-a-subjectaltname-sanucc-csr/