# 6 Definitions

#### Overview

While many things in the frontend can be configured using the frontend
itself, some customisations are currently only possible by editing a
definitions file.

This file is `defines.inc.php` located in /include of the Zabbix HTML
document directory.

#### Parameters

Parameters in this file that could be of interest to users:

-   ZBX\_LOGIN\_ATTEMPTS

Number of unsuccessful login attempts that is allowed to an existing
system user before a login block in applied (see ZBX\_LOGIN\_BLOCK). By
default 5 attempts. Once the set number of login attempts is tried
unsuccessfully, each additional unsuccessful attempt results in a login
block. Used with
[internal](/manual/web_interface/frontend_sections/administration/authentication)
authentication only.

-   ZBX\_LOGIN\_BLOCK

Number of seconds for blocking a user from accessing Zabbix frontend
after a number of unsuccessful login attempts (see
ZBX\_LOGIN\_ATTEMPTS). By default 30 seconds. Used with
[internal](/manual/web_interface/frontend_sections/administration/authentication)
authentication only.

-   ZBX\_PERIOD\_DEFAULT

Default graph period, in seconds. One hour by default.

-   ZBX\_MIN\_PERIOD

Minimum graph period, in seconds. One minute by default.

-   ZBX\_MAX\_PERIOD

Maximum graph period, in seconds. Two years by default since 1.6.7, one
year before that.

-   ZBX\_HISTORY\_PERIOD

The maximum period to display history data in *Latest data*, *Web*,
*Overview* pages and *Data overview* screen element in seconds. By
default set to 86400 seconds (24 hours). Unlimited period, if set to 0
seconds.

This constant value also affects how far in the past the value is
searched when {ITEM.VALUE} macro in trigger name is resolved (since
Zabbix 3.4.12).

-   GRAPH\_YAXIS\_SIDE\_DEFAULT

Default location of Y axis in simple graphs and default value for drop
down box when adding items to custom graphs. Possible values: 0 - left,
1 - right.

Default: 0

-   SCREEN\_REFRESH\_TIMEOUT (available since 2.0.4)

Used in screens and defines the timeout seconds for a screen element
update. When the defined number of seconds after launching an update
pass and the screen element has still not been updated, the screen
element will be darkened.

Default: 30

-   SCREEN\_REFRESH\_RESPONSIVENESS (available since 2.0.4)

Used in screens and defines the number of seconds after which query
skipping will be switched off. Otherwise, if a screen element is in
update status all queries on update are skipped until a response is
received. With this parameter in use, another update query might be sent
after N seconds without having to wait for the response to the first
one.

Default: 10

-   QUEUE\_DETAIL\_ITEM\_COUNT

Defines retrieval limit of the total items queued. Since Zabbix 3.2.4
may be set higher than default value.

Default: 500

-   ZBX\_SHOW\_SQL\_ERRORS (available since 3.4.0)

Show SQL errors in the frontend, if 'true'. If changed to 'false' then
SQL errors will still be displayed to all users with *Debug mode*
[enabled](/manual/config/users_and_usergroups/usergroup#configuration).
With *Debug mode* disabled, only Zabbix Super Admin users will see SQL
errors. Others will see a generic message: "SQL error. Please contact
Zabbix administrator."

Default: true

-   VALIDATE\_URI\_SCHEMES (available since 3.4.5)

Validate a URI against the scheme whitelist defined in
ZBX\_URI\_VALID\_SCHEMES.

Default: true

-   ZBX\_URI\_VALID\_SCHEMES (available since 3.4.2)

A comma-separated list of allowed URI schemes. Affects all places in the
frontend where URIs are used, for example, in map element URLs.

Default: http,https,ftp,file,mailto,tel,ssh

-   ZBX\_SHOW\_TECHNICAL\_ERRORS (available since 3.4.4)

Show technical errors (PHP/SQL) to non-Zabbix Super admin users and to
users that are not part of user groups with [debug
mode](/manual/web_interface/debug_mode) enabled.

Default: false