title: Apache proxypass URL to payment gateway returns to original URL
body: <p>Our internal apache reverse proxy server pointing to a 3rd party URL outside our org.
  <strong>Apache reverse proxy URL</strong>
  <a href="https://internalsite.com" rel="nofollow noreferrer">https://internalsite.com</a>
  <strong>3rd party site</strong>
  <a href="https://externalsite.com" rel="nofollow noreferrer">https://externalsite.com</a>
  <strong>Apache proxypass</strong>
  <a href="https://internalsite.com/external" rel="nofollow noreferrer">https://internalsite.com/external</a> --&gt; <a href="https://externalsite.com" rel="nofollow noreferrer">https://externalsite.com</a></p>
  <p>Proxy to external site working fine for all sub URIs except one test case,
  We have a payment option in 3rd party site.</p>
  <p>So users will hit <a href="https://internalsite.com/external" rel="nofollow noreferrer">https://internalsite.com/external</a> browse tru the option and hit payment which redirects to new URL <a href="https://paymentgateway.com" rel="nofollow noreferrer">https://paymentgateway.com</a>.
  User will key-in card details and hit pay. After payment successful from there its redirected to <a href="https://externalsite.com" rel="nofollow noreferrer">https://externalsite.com</a> and fails.</p>
  <p>Browser URL -&gt; <a href="https://externalsite.com/retByCard.do?resultIndicat0r=sadkjfhfsadjfhljas" rel="nofollow noreferrer">https://externalsite.com/retByCard.do?resultIndicat0r=sadkjfhfsadjfhljas</a>
  Browser message -&gt; ERROR_PROXY_AUTH_UNSUPPORTED</p>
  <p>I was expecting <a href="https://internalsite.com/external/retByCard.do?resultIndicat0r=sadkjfhfsadjfhljas" rel="nofollow noreferrer">https://internalsite.com/external/retByCard.do?resultIndicat0r=sadkjfhfsadjfhljas</a>
  Nothing logged in apache after the site is redirected to <a href="https://paymentgateway.com" rel="nofollow noreferrer">https://paymentgateway.com</a>, which is oblivious.</p>
  <p>Because the redirection if from paymentgateway.com this seems to be a dead end.
  Any workaround/solutions can be implemented in this scenario?</p>