Amazon EMR
Management Guide

Customize Proxy Agent Certificate

The proxy agent uses a self-signed Transport Layer Security (TLS) certificate by default. To use a custom certificate for the proxy agent, you must first obtain a certificate, certificate chain, and private key from your certificate authority. With those items, a PKCS12 file will be used to protect the key material so it can be imported into the proxy agent’s key store. The proxy agent is based on Apache Knox. You can replace the default certificate with your custom certificate using the following steps.

In the following steps, replace MasterPublicDNS with the value that appears for Master public DNS on the Summary tab of the cluster details pane. For example,

  1. To create a PKCS12 file from your certificate, certificate chain, and private key, run the following command on a host with the certificate files, and openssl installed.

    openssl pkcs12 -export -out proxy_agent_certificate.pfx -inkey private.key -in certificate.cer -certfile certchain.cer
  2. Copy the proxy_agent_certificate.pfx file to the /home/hadoop directory on the master node of your cluster.

    scp -i EC2KeyPair.pem proxy_agent_certificate.pfx hadoop@MasterPublicDNS:/home/hadoop
  3. SSH into the master node of your cluster.

    ssh -i EC2KeyPair.pem hadoop@MasterPublicDNS
  4. Find your cluster-specific master key by using the following command.

    less /etc/knox/conf/gateway-site.xml

    Look for the gateway.master.secret property and copy the contents of the value tag, as you will need it for future steps.

  5. Create a backup copy of the existing proxy agent keystores by using the following commands.

    sudo -s cd /mnt/var/lib/knox/data/security/keystores mkdir backups mv gateway.jks __gateway-credentials.jceks backups/
  6. Import your custom certificates into a new keystore by using the following commands.

    sudo -s cd /mnt/var/lib/knox/data/security/keystores keytool -importkeystore \ -srckeystore /home/hadoop/proxy_agent_certificate.pfx \ -srcstoretype pkcs12 -destkeystore gateway.jks \ -deststoretype jks \ -srcalias 1 \ -destalias gateway-identity

    When prompted for the Enter destination keystore password, use the Knox master secret from the gateway-site.xml file.

    Ensure the newly created gateway.jks file is owned by the knox user by using the following command.

    chown knox:knox gateway.jks

    If your private key is protected by a password, make sure Knox is aware of that password.

    sudo -u knox bash cd /usr/lib/knox bin/ create-cert create-alias gateway-identity-passphrase

    Enter the password protecting your private key when prompted.

  7. Restart Knox by using the following commands.

    sudo -u knox bash cd /usr/lib/knox bin/ stop

    Knox should be restarted automatically, and you can check the status of Knox by viewing the /var/log/knox/gateway.log.

  8. To ensure the new certificate is being used by the proxy agent, navigate to Apache Zeppelin https://MasterPublicDNS:8442/gateway/default/zeppelin/. You can use your browser to inspect the certificate to ensure it is your custom certificate.