Zabbix LLD not running after assigning template to Host (no Items/Triggers created)

[whanklee]

Hello,


I’d like to ask for your help to understand what might be wrong with the template and the Zabbix server configuration below. When I assign the template to a Host, nothing happens — it doesn’t run, and no new Items or Triggers appear. I have to restart the server, sometimes multiple times, before the LLD finally runs. There are no errors in the logs, but it still doesn’t execute.

zabbix_server.conf:

LogFile=/var/log/zabbix/zabbix_server.log
LogFileSize=0
PidFile=/run/zabbix/zabbix_server.pid
SocketDir=/run/zabbix
DBName=******
DBUser=******
DBPassword=*******
StartHTTPPollers=10
SNMPTrapperFile=/var/log/snmptrap/snmptrap.log
CacheSize=256M
CacheUpdateFrequency=60
HistoryCacheSize=128M
HistoryIndexCacheSize=32M
TrendCacheSize=32M
ValueCacheSize=128M
Timeout=4
FpingLocation=/usr/bin/fping
Fping6Location=/usr/bin/fping6
LogSlowQueries=3000
StartLLDProcessors=20
StatsAllowedIP=127.0.0.1
EnableGlobalScripts=1

zabbix_export:
version: '7.4'
template_groups:
- uuid: 5f30ef4d286b437d81f4419cb49ac1dd
name: WORK
- uuid: 7df96b18c230490a9a0a9e2307226338
name: Templates
templates:
- uuid: 4a6adadd8f8346c0ac3f88cadf290429
template: 'WP-Cron Monitor with Job Discovery'
name: 'WP-Cron Monitor with Job Discovery'
groups:
- name: WORK
- name: Templates
discovery_rules:
- uuid: f7e6b3a2f69e4f689f12b4a07ced7b26
name: 'WP-Cron sites discovery'
type: SCRIPT
key: wp.cron.discovery
delay: 1h
params: 'return ''{$WPCRON_SITES_JSON}'';'
item_prototypes:
- uuid: ce63ee9f350a47d79a975366e67fca09
name: 'WP-Cron JSON on {#SITE}'
type: HTTP_AGENT
key: 'wp.cron.json[{#SITE}]'
value_type: TEXT
url: 'https://{#SITE}/wp-json/monitor/cron'
headers:
- name: X-API-Key
value: '{$X_API_KEY:"{#SITE}"}'
tags:
- tag: WORK
value: WP-Cron
trigger_prototypes:
- uuid: ae25c55d47a448b3a17cda01766b020d
expression: 'nodata(/WP-Cron Monitor with Job Discovery/wp.cron.json[{#SITE}],10m)=1'
name: 'WP-Cron endpoint no data (10m) on {#SITE}'
priority: HIGH
tags:
- tag: WORK
value: WP-Cron
- uuid: 2fae8d5469884331aff2537aaeac66a4
name: 'WP-Cron now timestamp on {#SITE}'
type: DEPENDENT
key: 'wp.cron.now_ts[{#SITE}]'
units: unixtime
preprocessing:
- type: JSONPATH
parameters:
- $.now
master_item:
key: 'wp.cron.json[{#SITE}]'
tags:
- tag: WORK
value: WP-Cron
- uuid: b1f73ac3ad1b41d286a7d9ac1824f2ac
name: 'WP-Cron status on {#SITE}'
type: DEPENDENT
key: 'wp.cron.status[{#SITE}]'
value_type: TEXT
preprocessing:
- type: JSONPATH
parameters:
- $.status
master_item:
key: 'wp.cron.json[{#SITE}]'
tags:
- tag: WORK
value: WP-Cron
trigger_prototypes:
- uuid: 35c77e5f7cd1477496bf005fd2085741
expression: 'last(/WP-Cron Monitor with Job Discovery/wp.cron.status[{#SITE}])<>"ok"'
name: 'WP-Cron status is not OK on {#SITE}'
priority: WARNING
tags:
- tag: WORK
value: WP-Cron
- uuid: d638275756974003ba5977e54a4c6b13
name: 'WP-Cron Job discovery [{#SITE}]'
type: DEPENDENT
key: 'wp.cron.job.discovery[{#SITE}]'
item_prototypes:
- uuid: aab2a52895f541a0aebcd626c8a67ac1
name: 'WP-Cron Job Lag: {#JOB_HOOK} on {#SITE}'
type: CALCULATED
key: 'wp.cron.job.lag[{#SITE},{#JOB_HOOK}]'
value_type: FLOAT
units: s
params: '{#JOB_NEXT_RUN} - last(//wp.cron.now_ts[{#SITE}])'
tags:
- tag: Job
value: '{#JOB_HOOK}'
- tag: WORK
value: WP-Cron
trigger_prototypes:
- uuid: 0a3841c004e345bba59d46e5262edef1
expression: 'last(/WP-Cron Monitor with Job Discovery/wp.cron.job.lag[{#SITE},{#JOB_HOOK}]) < -{$WPCRON_OVERDUE_THRESHOLD}'
name: 'WP-Cron job ''{#JOB_HOOK}'' is overdue on {#SITE}'
priority: AVERAGE
tags:
- tag: Job
value: '{#JOB_HOOK}'
- tag: WORK
value: WP-Cron
parent_discovery_rule:
key: wp.cron.discovery
master_item:
key: 'wp.cron.json[{#SITE}]'
lld_macro_paths:
- lld_macro: '{#JOB_HOOK}'
path: $.hook
- lld_macro: '{#JOB_INTERVAL}'
path: $.interval
- lld_macro: '{#JOB_NEXT_RUN}'
path: $.next_run
- lld_macro: '{#JOB_SCHEDULE}'
path: $.schedule
preprocessing:
- type: JSONPATH
parameters:
- $.jobs
- type: DISCARD_UNCHANGED_HEARTBEAT
parameters:
- 1h
tags:
- tag: WORK
value: WP-Cron
macros:
- macro: '{$WPCRON_LAG_THRESHOLD}'
value: '900'
description: 'DEPRECATED (use WPCRON_OVERDUE_THRESHOLD)'
- macro: '{$WPCRON_OVERDUE_THRESHOLD}'
value: '300'
description: 'In seconds: trigger alert if job is overdue by this value (default: 5 minutes)'
- macro: '{$WPCRON_SITES_JSON}'
value: '{"data":[{"{#SITE}":"website1.hu"},{"{#SITE}":"website2.hu"}]}'
description: 'LLD JSON list of domains to be monitored'
- macro: '{$X_API_KEY:"website1.hu"}'
value: a86af02b-*******-d6a****f35b
- macro: '{$X_API_KEY:"website2.hu"}'
value: 4b3f040d-*******-88a****d48

Also, when I call the WordPress API, this is the response I receive:

{
    "status": "ok",
    "now": 1763716555,
    "jobs": [
        {
            "hook": "action_scheduler_run_queue_rucss",
            "next_run": 1763716530,
            "schedule": "every_minute",
            "interval": 60
        },
        {
            "hook": "wpcode_usage_tracking_cron",
            "next_run": 1764220609,
            "schedule": "weekly",
            "interval": 604800
        },
        {
            "hook": "newsletter_clean",
            "next_run": 1764264915,
            "schedule": "weekly",
            "interval": 604800
        }
    ]
}​

[Viktors Fomics]

Hello

I can see that the discovery rule has a delay of 1h, it might cause issues:

name: 'WP-Cron sites discovery'
type: SCRIPT
key: wp.cron.discovery
delay: 1h

I'd suggest setting up a shorter delay there for testing purposes: for example setting it to 1m and checking if the behaviour improves.

[whanklee]

Yes, I’m aware of that, and I already tried setting the delay to 1m, but it didn’t solve the problem. Nothing happened. The only thing that makes it run is restarting the Zabbix server and using zabbix_server -R config_cache_reload.

It feels like there is some kind of configuration issue on the server, but I haven’t been able to figure out what it could be.

[cyber]

I stumbled on this lately, did not work out, what was the issue, but it started to work after I just forced "execute now"... After that it stayed working a it should

[whanklee]

Yes, it also works for me if I trigger it manually, but I still can’t figure out why it needs to be executed manually in the first place.