Zabbix 7.0.5 on RHEL9, agent2 monitoring of postgres 17

Can confirm, Get bgwriter is not supported with Postgres 17:

Cannot fetch data: ERROR: column "checkpoints_timed" does not exist (SQLSTATE 42703). 

This also spams the postgres server log until you disable these items in the template.

This is small workaround patch zbx-25487.patch for zabbix-agent2-plugin-postgresql repository will fix the issue for Postgresql 17+. Patch is applicable for master and 6.0 branches. I did not try to apply for others.

It is better to split the stat by 2 separate: bgwriter and checkpointer. But it will break many setups.
 

With PG 17.4 and Zabbix 7.2.4 same issue

For me as a workaround i have used this query:

WITH checkpointer AS (
  SELECT
      num_requested AS checkpoints_req,
      num_timed AS checkpoints_timed,
      write_time AS checkpoint_write_time,
      sync_time AS checkpoint_sync_time,
      buffers_written AS buffers_checkpoint
  FROM pg_catalog.pg_stat_checkpointer
),
bgwriter AS (
  SELECT
      buffers_alloc,
      buffers_clean,
      maxwritten_clean
  FROM pg_catalog.pg_stat_bgwriter
)
SELECT jsonb_object_agg(key, value) AS row_to_json
FROM (
  SELECT 'checkpoints_req' AS key, checkpoints_req::text AS value FROM checkpointer
  UNION ALL
  SELECT 'checkpoints_timed', checkpoints_timed::text FROM checkpointer
  UNION ALL
  SELECT 'checkpoint_write_time', checkpoint_write_time::text FROM checkpointer
  UNION ALL
  SELECT 'checkpoint_sync_time', checkpoint_sync_time::text FROM checkpointer
  UNION ALL
  SELECT 'buffers_checkpoint', buffers_checkpoint::text FROM checkpointer
  UNION ALL
  SELECT 'buffers_alloc', buffers_alloc::text FROM bgwriter
  UNION ALL
  SELECT 'buffers_clean', buffers_clean::text FROM bgwriter
  UNION ALL
  SELECT 'maxwritten_clean', maxwritten_clean::text FROM bgwriter
) AS combined order by 1 ;

In handler_bgwriter.go and compiled it for 17 + versions.

I work with environment that editing/compile is not possible just wondering when that workaround comes to new version of agent2.

Personally me using that bash script from below to build patched version. Only pre-requirements for it is POSIX compatible OS with bash interpreter, with installed podman (or maybe docker), and also having access to the internet (to get the plugin source code using git and the patch by URL).

mkdir zabbix_plugin; cd zabbix_plugin
cat << 'EOF' | podman run -v "$(pwd):/go" -i --rm docker.io/golang:1.23.7-bookworm
apt -y update
apt -y install patch
git clone -b 7.0.10 --single-branch https://git.zabbix.com/scm/ap/postgresql.git
cd postgresql
patch plugin/handler_bgwriter.go <(curl -sL https://support.zabbix.com/secure/attachment/282233/282233_zbx-25487.patch)
make build
EOF 

After that i just taking postgresql/zabbix-agent2-plugin-postgresql and putting it onto servers at /usr/sbin/zabbix-agent2-plugin/ directory.

Pay attention, i'm using 7.0.10 version of zabbix-agent2. If you are going to use another one, you need to fix git clone -b value on your own.

Also pay attention to comment from bsa he wrote 14.02.20205, he said his patch is applicable for master and 6.0 branches in general (but works fine with 7.0.10 for me at least).

Filipp, do not edit your comment more, please. I have flooded by emails. 

Guys, just merge my patch. It works about month on at least 8 servers with zabbix-agent2 v6. It is very very simple change which do workaround for postgresql-17 statistics refactoring.

the patch is trivial, sjurgensons
what was the problem to release it in 7.0.11
?

Good day, Mr. itspief,

I understand your confusion, and I appreciate your patience.

There are several reasons behind the current situation:

Firstly, we’ve confirmed that the metrics buffers_backend and backend_fsync, which are no longer present in any statistics tables in PostgreSQL 17, cannot be aggregated from other available sources.

Secondly, addressing this issue involves not only updating the agent but also modifying the template. At the same time, we want to ensure that these changes do not negatively impact users running PostgreSQL versions earlier than 17 with the same setup.

Coordinating within the team and ensuring proper quality assurance takes some time, but it allows us to deliver a smooth and reliable experience for our users.

Best regards,
Stanislavs

Available in:

• 7.0.13rc1 3e3507ffec5
• 7.2.7rc1: 0c3430a84d2
• 7.4.0beta2:  f21d2e18279

Will it be merged to 6.x branches?

Good day, bsa.
Version 6 is in limited support.
This means that no new features are added to it.

You can read more about Zabbix lifecycle, and support policies here:
https://www.zabbix.com/life_cycle_and_release_policy

Best regards,
Staņislavs

Documentation updated: 

• What's new in Zabbix (7.0.13, 7.2.7)

Hello,

I noticed that in the new template for Zabbix 7.0.13 monitoring PostgreSQL 17.x via zabbix agent 2, the "pgsql.ping.time" is missing.

It is possible to add this as well in the new template ?

Best regards,

geo2022, Please open a separate ZBXNEXT for this to avoid mixing multiple requests in a single ticket. Thank you in advance.

Ok, no problem - new ZBXNEXT-10002

Thanks,