We have two servers librenms and librepoller01. librenms has MySQL, Memcached and RRDcacheD and the poller is configured to use the primary server for memcached, mysql and rrdcached. This setup was working, but then we had our systems team perform server upgrades on librepoller01 and this created an issue with rrdcached. Now none of the memory graphs work and we get errors in rrdcached. We had the systems team roll back the snapshot, but the error didn’t go away. Now when we run a poller.php on a host on the librepoller01 system we see “ERROR: rrdcached: Unknown command: last” and the logs have lots of lines like “Feb 16 14:31:29 librenms rrdcached[7186]: handle_request_update: stat (/opt/librenms/rrd/setzer293/storage-hrstorage-_dev_md19,_mounted_on___tmp.rrd) failed.”
[root@librepoller01 librenms]# sudo -u librenms ./validate.php
| Component | Version |
|---|---|
| LibreNMS | 21.2.0-1-g01019cfc0 |
| DB Schema | 2021_02_08_224355_fix_invalid_dates (199) |
| PHP | 7.4.12 |
| Python | 3.6.8 |
| MySQL | 5.5.60-MariaDB |
| RRDTool | 1.7.0 |
| SNMP | NET-SNMP 5.8 |
====================================
[OK] Composer Version: 2.0.9
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct
[INFO] Detected Python Wrapper
[OK] Connection to memcached is ok
[root@librenms librenms]# sudo -u librenms ./validate.php
| Component | Version |
|---|---|
| LibreNMS | 21.2.0-1-g01019cf |
| DB Schema | 2021_02_08_224355_fix_invalid_dates (199) |
| PHP | 7.3.12 |
| Python | 3.6.8 |
| MySQL | 5.5.60-MariaDB |
| RRDTool | 1.4.8 |
| SNMP | NET-SNMP 5.7.2 |
====================================
[OK] Composer Version: 2.0.9
[OK] Dependencies up-to-date.
[OK] Database connection successful
[OK] Database schema correct
[INFO] Detected Python Wrapper
[OK] Connection to memcached is ok