Fast Ping Checking Broken

Tags: #<Tag:0x00007f3b89876bc8>

I followed the exact steps at https://docs.librenms.org/Extensions/Fast-Ping-Check/ and now devices are constantly changing between down and up. Every 5 minutes, the device status changes to up, then 15 seconds later changes to down.

Relevant config settings:

$config['ping_rrd_step']=30;
$config['fping_options']['retries']=5;
$config['fping_options']['timeout']=1000;
$config['fping_options']['count']=5;
$config['fping_options']['millisec']=500;
$config['fping_options']['interval']=500;

./validate.php:

Component | Version
--------- | -------
LibreNMS  | 1.62.1
DB Schema | 2020_03_24_0844_add_primary_key_to_device_graphs (160)
PHP       | 7.2.19-0ubuntu0.18.04.2
MySQL     | 10.1.41-MariaDB-0ubuntu0.18.04.1
RRDTool   | 1.7.0
SNMP      | NET-SNMP 5.7.3
====================================

[OK]    Composer Version: 1.10.1
[OK]    Dependencies up-to-date.
[OK]    Database connection successful
[OK]    Database schema correct

/etc/cron.d/librenms:

SHELL=/bin/bash
PATH=/opt/librenms:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin

33   */6  * * *   librenms    /opt/librenms/cronic /opt/librenms/discovery-wrapper.py 1
*/5  *    * * *   librenms    /opt/librenms/discovery.php -h new >> /dev/null 2>&1
*/5  *    * * *   librenms    /opt/librenms/cronic /opt/librenms/poller-wrapper.py 4
*/5  *    * * *   librenms    /opt/librenms/poll-billing.php >> /dev/null 2>&1
01   *    * * *   librenms    /opt/librenms/billing-calculate.php >> /dev/null 2>&1
*/5  *    * * *   librenms    /opt/librenms/check-services.php >> /dev/null 2>&1
*    *    * * *   librenms    /opt/librenms/ping.php >> /dev/null 2>&1
*    *    * * *   librenms    sleep 30 && /opt/librenms/ping.php >> /dev/null 2>&1
*    *    * * *   librenms    sleep 15 && /opt/librenms/alerts.php >> /dev/null 2>&1
*    *    * * *   librenms    sleep 45 && /opt/librenms/alerts.php >> /dev/null 2>&1

# Daily maintenance script. DO NOT DISABLE!
# If you want to modify updates:
#  Switch to monthly stable release: https://docs.librenms.org/General/Releases/
#  Disable updates: https://docs.librenms.org/General/Updating/
15   0    * * *   librenms    /opt/librenms/daily.sh >> /dev/null 2>&1
*/5 * * * * librenms /opt/librenms/html/plugins/Weathermap/map-poller.php >> /dev/null 2>&1

What am I missing here?

Did you find what’s the issue?