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---
title: Zabbix
author: Christian Külker
date: 2022-06-07
version: 0.1.3
date: 2023-05-26
version: 0.1.4
type: doc
disclaimer: True
toc: True
Expand All @@ -29,9 +29,9 @@ with a PHP front end. Features are:
- sending alerts via e-mail, SMS and Jabber
- data stored in a relational database

[Zabbix] ships with an API for developers that provides access to almost all
functions in [Zabbix]. It supports a two-way integration with most other
software. The API can be used to integrate [Zabbix] functions into third-party
[Zabbix] ships with a developer API that provides access to almost all of the
functionality in [Zabbix]. It supports two-way integration with most other
software. The API can be used to integrate [Zabbix] functions into third party
software.

## Debian Packages
Expand All @@ -58,13 +58,13 @@ A `zabbix` client is called __agent__ in `zabbix` lingo.

## Installing Zabbix on Debian 10 Buster

The following instructions will try to be as generic as possible. This guide
will show how to install and configure the latest release (4.0.4) of [Zabbix]
Server on Debian 10 with a MySQL (MariaDB) database, PHP for the front end and
Apache Web Server 2 as the web interface. This is not the latest release that
would run on Debian 10 Buster. Since this is the official version for Debian 10
Buster, updates will be available. However it is possible to install newer
versions on Debian 10 Buster from the [Zabbix] web site.
The following instructions will try to be as general as possible. This guide
will show you how to install and configure the latest release (4.0.4) of the
[Zabbix] server on Debian 10 with a MySQL (MariaDB) database, PHP for the
frontend and Apache Web Server 2 for the web interface. This is not the latest
release that would run on Debian 10 Buster. Since this is the official release
for Debian 10 Buster, updates will be available. However, it is possible to
install newer versions on Debian 10 Buster from the [Zabbix] website.

### Zabbix 4.0.4 Server

Expand All @@ -74,7 +74,7 @@ Install the [Zabbix] server with MySQL (MariaDB) support.
aptitude install zabbix-server-mysql
```

Secure the database server (if not already done). The questions are
Back up the database server (if not already done). These questions are
self-explanatory.

```bash
Expand All @@ -92,9 +92,9 @@ FLUSH PRIVILEGES;
quit
```

Unfortunately the table definition of `host_inventory` has to be changed for
the table to fit into the mariadb 10.3 dynamic table format. (see
[row-size-too-large] for details)
Unfortunately, the table definition of `host_inventory` needs to be changed to
fit the mariadb 10.3 dynamic table format. (see [row-size-too-large] for
details).

Add the following two lines at the beginning of:
`/usr/share/zabbix-server-mysql/schema.sql.gz`
Expand All @@ -104,8 +104,9 @@ SET GLOBAL innodb_default_row_format='dynamic';
SET SESSION innodb_strict_mode=ON;
```

And at about line 1280 change all `varchar()` definition within the table
`host_inventory` with numbers smaller than 256 to 256 like so `varchar(256)`.
And at about line 1280, change all `varchar()` definitions within the
`host_inventory` table with numbers less than 256 to 256 like this
`varchar(256)`.


Populate the database
Expand All @@ -130,8 +131,8 @@ echo "DBUser=zabbix" >> /etc/zabbix/zabbix_server.conf
echo "DBPassword=CHANGE_ME" >> /etc/zabbix/zabbix_server.conf
```

In case you use a firewall you have to open port `tcp/10051`. There is also the
service `zabbix-server` for `firewalld`.
If you are using a firewall, you will need to open port `tcp/10051`. There is
also the service `zabbix-server` for `firewalld`.

### Zabbix 4.0.4 Front End

Expand All @@ -142,8 +143,8 @@ Remember to specify a PHP date.timezone in

#### Securing Zabbix 4.0.4 PHP Front End

To restrict the directories allowed to be read by your [Zabbix] PHP front end,
setting a PHP `open_basedir` directive is suggested.
To restrict the directories that are allowed to be read by your [Zabbix] PHP
frontend, setting a PHP `open_basedir` directive is suggested.

Put this example in your
`/etc/apache2/conf-available/zabbix-frontend-php.conf`, near the other
Expand All @@ -156,15 +157,15 @@ php_admin_value open_basedir /usr/share/zabbix/:/var/lib/zabbix:/etc/zabbix:\

### Setting Better Default Passwords

A one line command to set the `Admin` password.
A one-line command to set the `admin` password.

```bash
PW=`/usr/bin/pwgen -y -N 1 $((8 + RANDOM % 12 ))|/usr/bin/perl -pe 'chomp'`;\
echo "$PW";\
echo "update users set passwd=md5('$PW') where alias='Admin';"|mysql zabbix
```

A one line command to set the `guest` password.
A one-line command to set the `guest` password.

```bash
PW=`/usr/bin/pwgen -y -N 1 $((8 + RANDOM % 12 ))|/usr/bin/perl -pe 'chomp'`;\
Expand All @@ -174,26 +175,26 @@ echo "update users set passwd=md5('$PW') where alias='guest';"|mysql zabbix

## Zabbix 4.0.4 Client

The client in the [Zabbix] world is called `agent`. Installation is straight
forward.
The client in the [Zabbix] world is called an `agent`. Installation is
straightforward.

```bash
aptitude install zabbix-agent
```

Under Debian 10 Buster is the [Zabbix] client configured to use a [Zabbix]
server on `localhost`. Of course this is seldom the case. To use a different
server, add server IP to the entries of `Server` and `ServerActive` parameters
inside the client configuration `/etc/zabbix/zabbix_agentd.conf`.
On Debian 10 Buster, the [Zabbix] client is configured to use a [Zabbix] server
on `localhost`. Of course, this is rarely the case. To use a different server,
add the server IP to the entries of the `Server` and `ServerActive` parameters
in the client configuration `/etc/zabbix/zabbix_agentd.conf`.

In case you use a firewall you have to open port `tcp/10050`. There is also the
service `zabbix-agent` for `firewalld`.
If you are using a firewall, you will need to open port `tcp/10050`. There is
also the service `zabbix-agent` for `firewalld`.

There are different ways to add a client to the [Zabbix] server. One method is
to log into the web front end and select 'Configuration', 'Hosts' and press
the blue button `Create host` in the upper right corner. Add a template via
'Configuration' -> 'Host' -> click on host name under name column ->
'Templates' (of that host).
There are several ways to add a client to the [Zabbix] server. One method is to
log into the web frontend, select 'Configuration', 'Hosts' and press the blue
'Create Host' button in the top right corner. Add a template via
'Configuration' -> 'Host' -> click on the host name in the name column ->
'Templates' (of this host).

## Links

Expand All @@ -203,80 +204,83 @@ the blue button `Create host` in the upper right corner. Add a template via

## Critique Zabbix 4.0.4

While the installation of [Zabbix] is easy and straight forward and a lot of
data can be collected easily with templates and nice graphs can be made
visible, [Zabbix] 4.0.4 (and likely others) suffers from architecture
deficits, probably resulting from the very flexible data model.

- Automatic setup of Zabbix server templates differs from other servers
- Host groups do not allow to apply automatic template assignments
- Template assignments have to be done on a per host basis
- Not working/supported templates distributed (MySQL)
- Not working/supported templates can be chosen
- When chosen a not supported template [Zabbix] will not complain
- Working data queries are not always displayed, but only problems: seeing no
problems, do not mean that there is no problem, as some [Zabbix] problems are
discarded silently: this is a no go for a monitoring system (this forbids to
use [Zabbix] as the only monitoring system for an installation)
- No easy default graph setup. All graphs have to be chosen for each host
- No default dashboard/ overview over working services/data collection
- Encryption not default setup
- Discovered hosts can not be added via web interface
- Maps are not updated automatically (and not added/updated from database)
- Difficult to add templates/ data queries (for inexperienced people)
- Number of unsupported items are displayed in dashboard, but no link and
difficult to understand which item is not supported
- When adding a template to a host, not a button like "update" (as displayed
under the form) but the link "add" inside the form has to be clicked: this
breaks usability and is not intuitive. A button would be preferable.
- Naming of boxes are not intuitive: box 1 "Linked templates" and box 2 "Link
new template". Changing box 2 will update box 1. A different design with only
1 box would be better. Also the "add" link works as a **button** that do not
add something, but link a template. How confusing can it be?
- Some hosts added to host groups are shown in the inventory, but others are
not. This points to the fact that some concepts are not understandable via
the web interface and that some data dependency concepts are implicit and can
only be understood via a manual
- Most functions of the web interface have no default query, but need a manual
query. While this clearly has the advantage of flexibility, junior admins
would probably do not know what to query in the first place.
- Default query of Audit Report says 'no data'
- Default query of Action log Report says 'no data'
- No host specific reports
- When clicking a top level tab like "Monitoring" the sub level tab is updated,
but not the page content and a second click on the sub level tab has to be
performed. This is clearly a bug
While the installation of [Zabbix] is simple and straightforward, and a lot of
data can be easily collected with templates and nice graphs can be made
visible, [Zabbix] 4.0.4 (and probably others) suffers from architectural
shortcomings, probably resulting from the very flexible data model.

- Automatic setup of Zabbix server templates differs from other servers.
- Host groups don't allow automatic template assignments to be applied.
- Template assignments must be done on a per-host basis.
- Unsupported or non-working templates are distributed (MySQL).
- Unsupported or non-working templates can be selected.
- When an unsupported template is chosen, Zabbix doesn't issue a complaint.
- Working data queries aren't always displayed, only problems are. Not seeing
problems doesn't mean there aren't any, as some Zabbix issues are silently
ignored. This is unacceptable for a monitoring system, making Zabbix
unsuitable as the sole monitoring system for an installation.
- There's no simple default graph setup. All graphs must be chosen for each host.
- There's no default dashboard or overview of working services/data collection.
- Encryption isn't set up by default.
- Discovered hosts can't be added via the web interface.
- Maps aren't updated automatically and aren't added/updated from the database.
- It's difficult to add templates or data queries (especially for inexperienced
people).
- The number of unsupported items is displayed on the dashboard, but there's no
link and it's hard to understand which item is unsupported.
- When adding a template to a host, the "add" link inside the form should be
clicked, not an "update" button (as displayed under the form). This disrupts
usability and isn't intuitive. A button would be more preferable.
- The naming of boxes isn't intuitive: Box 1 is "Linked templates" and Box 2 is
"Link new template". Changing Box 2 will update Box 1. A different design
with only one box would be better. Additionally, the "add" link acts as a
__button__ that doesn't add something, but links a template. This can be
confusing.
- Some hosts added to host groups are shown in the inventory, but others
aren't. This suggests that some concepts can't be understood via the web
interface and that some data dependency concepts are implicit and can only be
understood through a manual.
- Most functions of the web interface don't have a default query, but require a
manual query. While this provides flexibility, junior admins may not know
what to query initially.
- The default query for the Audit Report indicates 'no data'.
- The default query for the Action Log Report indicates 'no data'.
- There are no host-specific reports.
- When clicking a top-level tab like "Monitoring", the sub-level tab updates,
but not the page content. A second click on the sub-level tab must be
performed. This is clearly a bug.
- ...

Therefore one get the impression that the web interface in its fresh installed
form is not programmed with the vision in mind to monitor computer systems but
to query a database in as many as possible ways.
Therefore, one gets the impression that the web interface in its freshly
installed form is not programmed with the vision of monitoring computer
systems, but of querying a database in as many ways as possible.

However, there are good preconfigured [Zabbix] instances that have a plethora
of graphs, dash boards and other aggregated data points from which a system
administrator can understand the situation (an not only the problems) of an
installation/cluster. As a consequence, there is a huge added value, for a
preconfigured [Zabbix] installation as some cluster administration stacks
of graphs, dashboards and other aggregated data points from which a system
administrator can understand the situation (and not just the problems) of an
installation/cluster. As a result, there is a huge added value to a
pre-configured [Zabbix] installation, such as some cluster management stacks
provide.

A word on [Zabbix] deployment. In case a preconfigured [Zabbix] server needs to
be deployed to many sites or if it has to be set up for a certain hardware
entity, like a rack or chassis (as a cluster entity for example), the [Zabbix]
server configuration lies mostly in its database and not in from of
configuration files. This means [Zabbix] has no separation of configuration and
process data. Therefore, if the configuration was only performed via the web
interface, the content of the database has to be duplicated and host
values/process data would need to be removed from the database for new hardware
entities. This also would make [Zabbix] updates very difficult. The solution or
an easy solution to this problem is not known to me, but seems like a major
problem. Other monitor systems like [Icinga2] or [Nagios] which are configured
via files can easily be distributed/cloned via git, puppet or other means, as
they separate process data from configuration data.
A word about [Zabbix] deployment. If a pre-configured [Zabbix] server needs to
be deployed to many sites, or if it needs to be set up for a specific hardware
entity such as a rack or chassis (e.g. as a cluster entity), the [Zabbix]
server configuration is mostly stored in its database and not in a set of
configuration files. This means that [Zabbix] has no separation between
configuration and process data. Therefore, if the configuration is done only
through the web interface, the database content would have to be duplicated and
host values/process data would have to be removed from the database for new
hardware entities. This would also make [Zabbix] updates very difficult. I am
not aware of a solution or a simple workaround for this problem, but it seems
to be a major issue. Other monitoring systems like [Icinga2] or [Nagios] which
are configured via files can be easily distributed/cloned via git, puppet or
other means as they separate process data from configuration data.

## History

| Version | Date | Notes |
| ------- | ---------- | ---------------------------------------------------- |
| 0.1.4 | 2023-05-26 | Improve writing |
| 0.1.3 | 2022-06-07 | Client explanation, shell->bash |
| 0.1.2 | 2020-12-27 | Critique Zabbix 4.0.4 |
| 0.1.1 | 2020-12-18 | Add hint for client configuration |
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