Manual:Create Certificates

Following is a step-by-step guide to creating your own CA (Certificate Authority) with openssl on Linux.

Generate certificates

• First step is to build the CA private key and CA certificate pair.

  openssl genrsa -des3 -out ca.key 4096
  openssl req -new -x509 -days 3650 -key ca.key -out ca.crt
  

  During the process you will have to fill few entries (Common Name (CN), Organization, State or province .. etc). Created CA certificate/key pair will be valid for 10 years (3650 days).

• Now create private-key/certificate pair for the server

  openssl genrsa -des3 -out server.key 4096
  openssl req -new -key server.key -out server.csr
  
  openssl x509 -req -days 3650 -in server.csr -CA ca.crt -CAkey ca.key -set_serial 01 -out server.crt
  

  And again during the process you will have to fill some entries. When filling CN remember that it must not match on CA and server certificate otherwise later naming collision will occur.

  

  Note: Common Name (CN) should match the DNS name, or the IP address of your server otherwise you will get "domain mismatch" message and for example Windows SSTP client will not be able to connect to the server.

  
  

• Client key/certificate pair creation steps are very similar to server. Remember to Specify unique CN.

  openssl genrsa -des3 -out client.key 4096
  openssl req -new -key client.key -out client.csr
  
  openssl x509 -req -days 3650 -in client.csr -CA ca.crt -CAkey ca.key -set_serial 01 -out client.crt
  

Import certificates

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