Export from JKS to PKCS #12.
keytool -importkeystore -srckeystore keystore.jks -destkeystore keystore.p12 -deststoretype PKCS12 -srcalias <jkskeyalias> -deststorepass <password> -destkeypass <password>
mv keystore.p12 /root
cd /root
convert to key
openssl rsa -outform der -in private.pem -out private.key
nano /etc/httpd/conf.d/ssl.conf
find the line <VirtualHost _default_:443>
uncomment ServerName and type servername:443
uncomment:
SSLEngine on
SSLCertificateFile /root/downloadedcertificate.crt
SSLCertificateKeyFile /root/private.key
save and exit
restart httpd
service httpd restart
then test
then