Apache proxypass https to https

Question

here is what I tired to do:

1. browser -internet-> https(Apache proxypass)-intranet->(Apache https)
2. both Apaches are installed the ssl certs.(startssl wide card,not self-signed)

Apache error log:

[client 192.168.2.157] SSL Proxy requested for test.xxx.com:443 but not enabled [Hint: SSLProxyEngine]

[error] proxy: HTTPS: failed to enable ssl support for 192.168.2.157:443 (test.xxx.com)

Then I tried use apache(on the internet) proxy to https://google.com and the error log is the same.

However，https to http works. browser -internet-> https(Apache proxypass)-intranet->(Apache http)

My config:

<VirtualHost  *:443>
    SSLEngine on
    SSLCertificateFile /etc/apache2/ssl/xxx_com.crt
    SSLCertificateKeyFile /etc/apache2/ssl/xxx_com.key
    SSLCertificateChainFile /etc/apache2/ssl/sub.class2.server.ca.pem
    ProxyPreserveHost On
    ProxyRequests Off
    ProxyVia Off
    AllowEncodedSlashes NoDecode
    <Proxy *>
    Order deny,allow
    Allow from all
    </Proxy>
    ProxyPass  /       https://2w.xxx.com/
    ProxyPassReverse   /       https://2w.xxx.com/
    ServerName test.xxx.com
    RequestHeader set X-Forwarded-Proto "https"
    RequestHeader set X-Forwarded-Port "443"
    ErrorLog "/var/log/apache2/error-ssl.log"
</VirtualHost>

OR:

<VirtualHost  *:443>
    ProxyPass  /       https://google.com/
    ProxyPassReverse   /       https://google.com/
    SSLEngine on
    SSLCertificateFile /etc/apache2/ssl/xxx_com.crt
    SSLCertificateKeyFile /etc/apache2/ssl/xxx_com.key
    SSLCertificateChainFile /etc/apache2/ssl/sub.class2.server.ca.pem
    ServerName test.xxx.com
</VirtualHost>

Seems like it's not possible for apache to handle https to https? if apache does not support this how about nginx?

You should set "SSLProxyEngine On". The following is my example that may give you any idea.

<VirtualHost *:443>
    SSLEngine On
    SSLProxyEngine On
    ServerName my.example.com:443
    SSLCertificateFile "${SRVROOT}/conf/ssl/example.pem"
    SSLCertificateKeyFile "${SRVROOT}/conf/ssl/example.key"
    ErrorLog "|bin/rotatelogs.exe -l /var/logs/apache/example/error.%Y-%m-%d.log 86400"
    CustomLog "|bin/rotatelogs.exe -l /var/logs/apache/example/ssl_request.%Y-%m-%d.log 86400" \
        "%t %h %{SSL_PROTOCOL}x %{SSL_CIPHER}x \"%r\" %b"

    ProxyRequests Off
    ProxyPass / https://www.google.com/
    <Location />
        ProxyPassReverse /

        Options FollowSymLinks
        Require all granted
    </Location>   
</VirtualHost>