Fixing Slow Loading Pages and Graphs in LibreNMS by Removing Unicast Port Monitoring from Port Polling

If you’re managing a network with a mixed environment of HP and Juniper switches, you may already be familiar with the power of LibreNMS, a popular network monitoring tool that provides real-time insights into network performance. However, if you’re in the process of rolling out more Juniper EX3400 switches and have noticed a sudden decrease in performance, you may be wondering what’s causing the issue.

I came across this information somewhere, but I am unable to locate the source now. However, to resolve the issue, you only need to add comment symbols to two lines in the file below:

sudo nano includes/polling/ports.inc.php

Add the comment forward slashes “//” to both lines in the $shared_oids section :

• ‘ifInNUcastPkts’,
• ‘ifOutNUcastPkts’,

$shared_oids = [
    'ifInErrors',
    'ifOutErrors',
//    'ifInNUcastPkts',
//    'ifOutNUcastPkts',
    'ifInDiscards',
    'ifOutDiscards',
    'ifPhysAddress',
    'ifLastChange',
    'ifType',
    'ifMtu',
];

Save the file and be patient for a few minutes. Soon, your website should be loading swiftly once more.

Note: After modifying a file, the program may cease to update, resulting in the following error message:

How to solve this issue

1. Create a backup of the modified file by copying it to the /tmp directory or another location of your choice:
2. Restore the original version of the modified file using git checkout: git checkout includes/polling/ports.inc.php
3. Execute the ./daily.sh script to update the application and restore the file
4. Open and edit the includes/polling/ports.inc.php file, adding the desired comments, and save the changes. Do not copy the old file back, as it may cause permission issues
5. The modifications made to the file will be ignored by the application going forward.