<li class="">
    <a href="{{ Config::get('syntara::config.uri') }}/logviewer">
        <i class="glyphicon glyphicon-list-alt"></i><span>Logs</span>
    </a>
</li>
<li class="">
    <a href="{{ URL::to(Config::get('syntara::config.uri') }}.'/logviewer')}}">
        <i class="glyphicon glyphicon-list-alt"></i><span>Logs</span>
    </a>
</li>

Change URL log viewer on navigation
Change URL log viewer on navigation