Backup failing

Hi,

I've setup backup to S3 but keep getting an error when manually initiating the backup (it doesn't run automatically either). Maybe I've set it up incorrectly. Hoping someone can point me in the right direction. My steps:

• Created S3 bucket
• Added S3 credentials (Access Key ID and Secret Key) to runway.php
• Added bucket parameters to buckets.php
• Setup backup in the control panel, selecting my bucket from the dropdown (it is the only entry)

Here is my buckets.php:

<?php
    return [
        'backups' => [
                 'type'      => 'amazon_s3',
                 'region'    => 'us-east-1',
                 'web_path'  => 'https://s3.amazonaws.com/[bucketname]',
                 'file_path' => '[bucketname]',
         ],
    ]

        ?>

And here are the short diagnostics:

Perch Runway: 3.0.4, PHP: 5.4.45, MySQL: 5.5.54, with MySQLi Server OS: Linux, cgi-fcgi Installed apps: content (3.0.4), assets (3.0.4), categories (3.0.4), perch_gallery (2.8.9) App runtimes: <?php $apps_list = array( 'content', 'categories', 'perch_gallery', ); PERCH_LOGINPATH: redacted PERCH_PATH: /home/innosofus/public_html/content PERCH_CORE: /home/innosofus/public_html/content/core PERCH_RESFILEPATH: /home/innosofus/public_html/content/resources Image manipulation: GD PHP limits: Max upload 20M, Max POST 8M, Memory: 128M, Total max file upload: 8M F1: 0c66c2e1f82f9e0b7617b2cb8270f2c7 Resource folder writeable: Yes DOCUMENT_ROOT: /home/innosofus/public_html HTTP_HOST: redacted-domain-name.com REQUEST_URI: /content/core/settings/diagnostics/ SCRIPT_NAME: /content/core/settings/diagnostics/index.php

And the error message is:

Fatal error: Class 'PDO' not found in /home/innosofus/public_html/content/core/runway/lib/vendor/rah/danpu/src/Rah/Danpu/Dump.php on line 116

Thanks in advance,

Matt