Monday, February 8, 2016

How to install a SSL certificate in Tomcat 8

If you want to run your web app on Tomcat 8 (Linux) under the HTTPS umbrella, these are the steps that you need to follow. In this example we will use test domain

1) Purchase an SSL certificate from trusted provider. Price ranges from $5 to over $100 per year.

2) SSH to your Linux server and, from your personal directory /home/youruser/ type the following command in order to generate the private key:
keytool -genkey -alias tomcat -keyalg RSA -keystore example.keystore

3) You will be asked some questions. The most important ones are the keystore password (let's assume it is yourPassword) and the First and last names, which is actually misleading because you need to enter the domain name:

4) Generate your local Certificated Signing Request (CSR) with this command:
keytool -certreq -keyalg RSA -alias tomcat -file example.csr -keystore example.keystore

5) Open the CSR file that you have just generated with vim example.csr, select all the content and copy it to the clipboard.

6) Paste the CSR from your clipboard in your trusted provider's website in order to issue the SSL certificate.

7) You will receive an email with a root certificate, at least one intermediate certificate and a signed certificate in CRT format.

8) Transfer all these files to the /home/youruser/ directory in the server using a FTP tool such as Filezilla.

9) Import the root certificate:
keytool -import -alias root -keystore example.keystore -trustcacerts -file yourRootCertificate.crt

10) Import each intermediate certificate (with a different alias):
keytool -import -alias intermediate1 -keystore example.keystore -trustcacerts -file yourFirstIntermediateCert.crt
keytool -import -alias intermediate2 -keystore
example.keystore -trustcacerts -file yourSecondIntermediateCert.crt

11) Import your signed certificate:
keytool -import -alias tomcat -keystore example.keystore -file yourSignedCert.crt

12) From the tomcat8/conf/server.xml file, add or edit the following code:
<Connector port="8443" maxThreads="150" scheme="https" secure="true"
           SSLEnabled="true" keystoreFile="/home/youruser/example.keystore"                   keystorePass="yourPassword" clientAuth="false" 
           keyAlias="tomcat" sslProtocol="TLS"/>

13) If you want to force the HTTPS to be loaded at all times, change the redirect of port 8080 in server.xml to 443. And add the following code in web.xml inside the <web-app>:
<!-- Require HTTPS for everything except /img (favicon) and /css. -->

14) If you are using a hosting provider such as Microsoft Azure, you will need to map the private and public ports in the virtual machine and upload the CRT certificates in the cloud service, as per below :

15) Your service should be available now on, and automatically redirected to the HTTPS version from