Alerts hidden on overview page

[Neal.H]

Hi All,

I'm stuck with a problem in Zabbix 5.0.1 that makes no sense to me - so am probably missing something obvious.

I have two systems that currently have open alerts - the Zabbix server (OS changed after upgrade/reboot, waiting for ACK) and a switch with some ports in half duplex. All show as I would expect on the dashboard and problem list. However the Overview page only shows the Zabbix server alert. I can get it to show the switch alerts if I select that device in the hosts list, or a host group the switch is in, but after removing all filters it does not show.

I'm fully up to date as of CentOS7 with Zabbix repo, have rebooted the zabbix server, deleted and recreated the switch, removed it from all host groups, logged in as the Admin user etc but not been able to get those alerts to show on the overview with no filters selected. I've also not found anything on the bug list that seems similar. This is a new demonstration deployment so I do not know if any other alerts would have the same issue.

Any pointers greatly appreciated.

Cheers,
Neal.

[Neal.H]

Hi All,

Some further information: I now have a few more alerts triggering and it seems that all alerts from the switches are hidden on the overview are based on the number of hosts in the group. If I create a host group with just the switches in and filter to that group the alerts are shown. If I add more hosts to the group then I get to the point where each host I add to the group hides one of the switches alerts.

Screenshots attached showing:
- full problem list (4 switches with triggers)
- overview with no filters (no switches visible)
- overview filtered to group with 53 hosts (all 4 switches show)
- overview filtered to group with 54 hosts (only 3 switches show)

I tried increasing my users "Rows per page" to 60 with no change.

Something seems to be truncating the list of hosts in the overview - causing some hosts to be hidden if there are a large number. I have 73 hosts in my setup, and so far have only seen this occur for the snmp monitored devices (although most devices are not generating errors so that could be coincidence)

Problems page shows all problems correctly:


Trigger overview with no filters does not show any switch problems:


Trigger overview filtered to a group with 53 hosts shows all 4 switch problems:


Trigger overview filtered to group with 54 hosts hides one of the switches (switch5-c) problems:


Switch5-c is in both groups:

[Simon.S]

Hello,

we have the same problem since our update yesterday from version 4.0.22 to 5.0.1.

OS is a fully patched Ubuntu 18.04.4 LTS with mariadb 10.2.32.

If I only add certain groups to the overview, all problems are displayed.

The error is felt to occur when the total number of hosts in the groups exceeds a certain limit. After that, only the problems of the first hosts (sorted alphabetically) are displayed.

I see the problem with hosts monitored by zabbix agent as well as web monitoring and SNMP.

[Simon.S]

I found a weird sql query in debug mode

SELECT h.hostid,h.name FROM hosts h WHERE h.flags IN (0,4) AND h.status IN (0,1) ORDER BY h.name LIMIT 51

Is there a way to change the "LIMIT" value? i have already tried
"Max count of elements to show inside table cell"
and "Rows per page", but without success.

[Simon.S]

I think I found the problem.

The LIMIT is set in

/usr/share/zabbix/defines.inc.php

as

ZBX_MAX_TABLE_COLUMNS

If I increase the value from 50 to 200 I see all triggers in the overview

[Neal.H]

Confirmed, well spotted. My files is at /usr/share/zabbix/include/defines.inc.php

// Applied to tables with variable count of columns. Columns above this limit will be truncated.
define('ZBX_MAX_TABLE_COLUMNS', 50);

Increasing that number to > host count seems to bypass the problem. I did not experience this with previous versions of Zabbix so seems like a bug with 5.0. I'm not sure what the implications of this are for system performance though.

[Neal.H]

Another similar issue on the latest data page: https://www.zabbix.com/forum/zabbix-...n-data-missing

This feels like a bug to me, raised as such - https://support.zabbix.com/browse/ZBX-17948

[Jiri Hadamek]

I have tried to raise default 50 to 500 (more than our number of hosts) in https://www.zabbix.com/forum/zabbix-troubleshooting-and-problems/403544-latest-data-selection-data-missing and the problem persists

// Applied to tables with variable count of columns. Columns above this limit will be truncated.
define('ZBX_MAX_TABLE_COLUMNS', 50);)

default 50 to 500 (more than our number of hosts) and problem persists.

[evaristo.quintao]

Hi,

Have you tried increase the values from Administration > General > GUI in fields ?


"Max number of columns and rows in overview tables"

and maybe:

"Limit for search and filter results";

[Wiegand]

I’m having the same problem...left a subreddit but I’m getting notifications from it.