---
title: ALPN filter for overriding ALPN for upstream TLS connections.
layout: protoc-gen-docs
generator: protoc-gen-docs
number_of_entries: 3
---
<h2 id="FilterConfig">FilterConfig</h2>
<section>
<p>FilterConfig is the config for Istio-specific filter.</p>

<table class="message-fields">
<thead>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr id="FilterConfig-alpn_override">
<td><div class="field"><div class="name"><code><a href="#FilterConfig-alpn_override">alpn_override</a></code></div>
<div class="type"><a href="#FilterConfig-AlpnOverride">AlpnOverride[]</a></div>
</div></td>
<td>
<p>Map from upstream protocol to list of ALPN</p>

</td>
</tr>
</tbody>
</table>
</section>
<h3 id="FilterConfig-AlpnOverride">AlpnOverride</h3>
<section>
<table class="message-fields">
<thead>
<tr>
<th>Field</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr id="FilterConfig-AlpnOverride-upstream_protocol">
<td><div class="field"><div class="name"><code><a href="#FilterConfig-AlpnOverride-upstream_protocol">upstream_protocol</a></code></div>
<div class="type"><a href="#FilterConfig-Protocol">Protocol</a></div>
</div></td>
<td>
<p>Upstream protocol</p>

</td>
</tr>
<tr id="FilterConfig-AlpnOverride-alpn_override">
<td><div class="field"><div class="name"><code><a href="#FilterConfig-AlpnOverride-alpn_override">alpn_override</a></code></div>
<div class="type">string[]</div>
</div></td>
<td>
<p>A list of ALPN that will override the ALPN for upstream TLS connections.</p>

</td>
</tr>
</tbody>
</table>
</section>
<h3 id="FilterConfig-Protocol">Protocol</h3>
<section>
<p>Upstream protocols</p>

<table class="enum-values">
<thead>
<tr>
<th>Name</th>
<th>Description</th>
</tr>
</thead>
<tbody>
<tr id="FilterConfig-Protocol-HTTP10">
<td><code><a href="#FilterConfig-Protocol-HTTP10">HTTP10</a></code></td>
<td>
</td>
</tr>
<tr id="FilterConfig-Protocol-HTTP11">
<td><code><a href="#FilterConfig-Protocol-HTTP11">HTTP11</a></code></td>
<td>
</td>
</tr>
<tr id="FilterConfig-Protocol-HTTP2">
<td><code><a href="#FilterConfig-Protocol-HTTP2">HTTP2</a></code></td>
<td>
</td>
</tr>
</tbody>
</table>
</section>