Installing an SSL Certificate on a Tomcat Server

This section describes how to install an SSL certificate on a Linux Tomcat 7 server. The installation process is similar for other Tomcat servers. When the certificate is installed, it secures communication between your server and the client through SSL.

The installation procedure in this topic is for your reference only as the commands executed and configuration file modified during the installation may vary depending on OS types and server configurations.

Prerequisites

The certificate has been issued and the certificate status is Issued.
You have downloaded the SSL certificate. For details, see Downloading a Certificate.
You have installed the OpenSSL tool.
Download the latest OpenSSL installation package from https://www.openssl.org/source/. The OpenSSL must be 1.0.1g or later.
You have installed Keytool.
Keytool is typically included in the Java Development Kit (JDK) tool package.
Ensure that the certificate matches all the domain names to be protected. For details about how to add or modify a domain name, see How Do I Add, Unbind, Replace, or Change the Domain Name for an SSL Certificate?.

Constraints

Before installing the certificate, enable port 443 on the server where the SSL certificate is installed and add port 443 to the security group. Otherwise, HTTPS cannot be enabled after the installation.
If a domain name maps to multiple servers, deploy the certificate on each server.
An SSL certificate can only be installed on the server that maps to the domain name associated with the certificate. Otherwise, the web browser will display a message indicating that the connection to the domain name is insecure.

Procedure

The installation process is as follows (for Tomcat 7 servers):

Step 1: Obtain Files → Step 2: Create a Directory → Step 3: Modify the Configuration File → Step 4: Restart Tomcat → Step 5: Verify the Effect

Step 1: Obtain Files

Before installing a certificate, obtain the certificate file and password file. Perform the following operations based on the value selected for CSR when applying for a certificate:

If you select System generated CSR for CSR when applying for a certificate, perform the operations according to the instructions in System generated CSR.
If you select Upload a CSR for CSR when applying for a certificate, perform the operations according to the instructions in Upload a CSR.

Detailed operations are as follows:

System generated CSR
1. Decompress the downloaded certificate file on your local PC.
  The downloaded file contains the Apache, IIS, Nginx, Tomcat, and Pem folders as well as the domain.csr file. Figure 1 shows an example.
  Figure 1 Decompressing an SSL certificate package on a local computer
2. Obtain Certificate ID_Domain name bound to the certificate_server.jks and Certificate ID_Domain name bound to the certificate_keystorePass.txt from Certificate ID_Domain name bound to the certificate_Tomcat.
Upload a CSR
1. Decompress the downloaded certificate package to obtain the Certificate ID_Domain name bound to the certificate_server.pem file.
  The Certificate ID_Domain name bound to the certificate_server.pem file contains two segments of certificate codes -----BEGIN CERTIFICATE----- and -----END CERTIFICATE-----, which are the server certificate and intermediate CA certificate respectively.
2. Use OpenSSL to convert the PEM certificate into a PFX certificate and obtain the server.pfx file.
  1. Save the PEM certificate and the private key server.key generated during CSR generation to the bin directory in the OpenSSL installation directory.
  2. In the bin directory of the OpenSSL installation directory, run the following command to convert the PEM certificate into a PFX certificate and press Enter:
    openssl pkcs12 -export -out server.pfx -inkey server.key -in CertificateID_DomainNameBoundToCertificate_server.pem
    
    The following message is displayed.
```
Enter Export Password:
```
  3. Enter the password of the PFX certificate and press Enter.
    The password is user-defined. Set it as required.
    
    The following message is displayed.
```
Verifying - Enter Export Password:
```
    Remember the PFX certificate password. The JKS password must be the same as the PFX password. Otherwise, Tomcat may fail to start.
    To improve password security, set the password based on the following rules:
    - Contain 8 to 32 characters.
    - Must contain at least three types of the following characters: uppercase letters, lowercase letters, digits, and special characters ~`!@#$%^&*()_+|{}:"<>?-=\[];',./
  4. Re-enter the password of the PFX certificate and press Enter.
    If no error information is displayed, the server.pfx file has been generated in the OpenSSL installation directory.
3. Use Keytool to convert the PFX certificate into a JKS certificate and obtain the server.jks file.
  1. Copy the server.pfx file generated in 2 to the %JAVA_HOME%/jdk/bin directory.
  2. In the %JAVA_HOME%/jdk/bin directory, run the following command and press Enter:
    keytool -importkeystore -srckeystore server.pfx -destkeystore server.jks -srcstoretype PKCS12 -deststoretype JKS
    
    The following message is displayed.
```
Enter the destination keystore password:
```
  3. Enter the password of the JKS certificate and press Enter.
    Set the password of the JKS certificate to the same as that of the PFX certificate. Otherwise, Tomcat may fail to start.
    
    The following message is displayed.
```
Enter the password again:
```
  4. Re-enter the password of the JKS certificate and press Enter.
    The following message is displayed.
```
Enter the source keystore password:
```
  5. Enter the password of the PFX certificate set in 2.c and press Enter.
    If information similar to the following is displayed, the conversion is successful and the server.jks file has been generated in the OpenSSL installation directory.
```
Entry for alias 1 imported successfully.
Import command completed: 1 entry successfully imported, 0 entries failed or canceled
```
  6. Create a keystorePass.txt file in the %JAVA_HOME%/jdk/bin directory and save the password of the JKS certificate in the file.
4. Place the converted certificate file server.jks and the new password file keystorePass.txt in the same directory.

Step 2: Create a Directory

Create a cert directory in the Tomcat installation directory, and copy the server.jks and keystorePass.txt files to the cert directory.

Step 3: Modify the Configuration File

Before modifying the configuration file, back up the configuration file. You are advised to deploy the configuration file in the test environment and then configure it on the production environment to avoid service interruptions caused by incorrect configurations.

The process of configuring an SSL certificate for Tomcat is similar across different versions. However, the configuration details may vary depending on the Java runtime environment and the format of the configuration file. The following uses Tomcat 7 as an example to describe how to modify the configuration file.

The installation process is as follows (for Tomcat 7 servers):

Find the following parameters in the server.xml file in the Tomcat installation directory conf:

<!--
    <Connector port="8443" protocol="org.apache.coyote.http11.Http11Protocol"
               maxThreads="150" SSLEnabled="true" scheme="https" secure="true"
               clientAuth="false" sslProtocol="TLS" />
    -->

Find the preceding parameters and delete the comment characters <!- - and - ->.

Add the following parameters. Change the values of the parameters according to Table 1.

keystoreFile="cert/server.jks"
keystorePass="Certificate key"

The complete example configuration is as follows. Modify other parameters based on your needs.

<Connector port="443" protocol="org.apache.coyote.http11.Http11Protocol"
               maxThreads="150" SSLEnabled="true" scheme="https" secure="true"
      keystoreFile="cert/server.jks"
    keystorePass="Certificate key"
      clientAuth="false" sslProtocol="TLS" />

Do not directly copy all configuration. Only parameters keystoreFile and keystorePass need to be added. Set other parameters based on site requirements.

**Table 1** Parameter description (1)
Parameter	Description
port	Port number to be used on the server. You are advised to set the value to 443.
protocol	HTTP protocol. Retain the default value.
keystoreFile	Path for storing the server.jks file. The value can be an absolute path or a relative path. Example: cert/server.jks
keystorePass	Password of server.jks. Set this parameter to the password provided in the keystorePass.txt file. If the password contains &, replace it with & to avoid configuration failure. An example command is provided as follows: If the password is keystorePass="Ix6&APWgcHf72DMu", change it to keystorePass="Ix6&APWgcHf72DMu".
clientAuth	Whether to require all customers to show the security certificate and authenticate their identity. Retain the default value.

Find the following parameters in the server.xml file in the Tomcat installation directory conf:
```
<Host name="localhost"  appBase="webapps"
      unpackWARs="true" autoDeploy="true">
```
Change the value of Host name to the domain name bound to the certificate.
The complete configuration is as follows (www.domain.com is used as an example):
```
<Host name="www.domain.com"  appBase="webapps"
      unpackWARs="true" autoDeploy="true">
```
Save the configuration file.

If the Tomcat fails to be started and the error Keystore was tampered with, or password was incorrect is recorded in the log, ensure that the following settings are correct:

The certificate password configured in server.xml is the password in the keystorePass.txt file. For details about how to set the file password, see Table 1.
The keystoreFile file path is correct.
The user running Tomcat must have read permissions for the certificate file.

Step 4: Restart Tomcat

Run the ./shutdown.sh command in the bin directory of Tomcat to stop the Tomcat service.

After 10 seconds, run the ./startup.sh command to start the Tomcat service. If the process is automatically started by the daemon process, you do not need to manually start the process.