See also: Compilation issues.
zabbix_proxy on MySQL versions 8.0.0-8.0.17 fails with the following "access denied" error:
[Z3001] connection to database 'zabbix' failed: [1227] Access denied; you need (at least one of) the SUPER, SYSTEM_VARIABLES_ADMIN or SESSION_VARIABLES_ADMIN privilege(s) for this operation
That is due to MySQL 8.0.0 starting to enforce special permissions for setting session variables. However, in 8.0.18 this behavior was removed: As of MySQL 8.0.18, setting the session value of this system variable is no longer a restricted operation.
The workaround is based on granting additional privileges to the zabbix
user:
For MySQL versions 8.0.14 - 8.0.17:
For MySQL versions 8.0.0 - 8.0.13:
The sql_mode
setting in MySQL/MariaDB must have the "STRICT_TRANS_TABLES" mode set. If it is absent, the Zabbix database upgrade will fail (see also ZBX-19435).
Upgrading Zabbix may fail if database tables were created with MariaDB 10.2.1 and before, because in those versions the default row format is compact. This can be fixed by changing the row format to dynamic (see also ZBX-17690).
In dual-stack environments (systems configured to support both IPv4 and IPv6), the hostname localhost
typically resolves to both IPv4 and IPv6 addresses. Due to the common prioritization of IPv6 over IPv4 by many operating systems and DNS resolvers, Zabbix templates may fail to work correctly if the service being monitored is configured to listen only on IPv4.
Services that are not configured to listen on IPv6 addresses may become inaccessible, leading to monitoring failures. Users might configure access correctly for IPv4 but still face connectivity issues due to the default behavior of prioritizing IPv6.
A workaround for this is to ensure that the services (Nginx, Apache, PostgreSQL, etc.) are configured to listen on both IPv4 and IPv6 addresses, and Zabbix server/agent is allowed access via IPv6. Additionally, in Zabbix templates and configurations, use localhost
explicitly instead of 127.0.0.1
to ensure compatibility with both IPv4 and IPv6.
For example, when monitoring PostgreSQL with the PostgreSQL by Zabbix agent 2 template, you may need to edit the pg_hba.conf
file to allow connections for the zbx_monitor
user. If the dual-stack environment prioritizes IPv6 (system resolves localhost to ::1
) and you configure localhost
but only add an IPv4 entry (127.0.0.1/32
), the connection will fail because there is no matching IPv6 entry.
The following pg_hba.conf
file example ensures that the zbx_monitor
user can connect to any database from the local machine using both IPv4 and IPv6 addresses with different authentication methods:
# TYPE DATABASE USER ADDRESS METHOD
host all zbx_monitor localhost trust
host all zbx_monitor 127.0.0.1/32 md5
host all zbx_monitor ::1/128 scram-sha-256
If necessary, you can also use the IPv4 address (127.0.0.1
) directly when configuring the PostgreSQL by Zabbix agent 2 template macro for the connection string.
With EPEL repository installed and enabled, installing Zabbix from packages will lead to EPEL Zabbix packages being installed rather than official Zabbix packages.
In this case uninstall Zabbix packages from EPEL, i.e.:
Block Zabbix packages from EPEL. Add the following line in the /etc/yum.conf
file:
Install Zabbix server again:
Notice that official Zabbix packages have the word release
in their version string:
When installing Zabbix from Red Hat Enterprise Linux packages on Red Hat Universal Base Image environments, ensure access to required repositories and dependencies. Zabbix packages depend on libOpenIPMI.so
and libOpenIPMIposix.so
libraries, which are not provided by any package in the default package manager repositories enabled on UBI systems and will result in installation failures.
The libOpenIPMI.so
and libOpenIPMIposix.so
libraries are available in the OpenIPMI-libs
package, which is provided by the redhat-#-for-<arch>-appstream-rpms
repository. Access to this repository is curated by subscriptions, which, in the case of UBI environments, get propagated by mounting repository configuration and secrets directories of the RHEL host into the container file-system namespace.
For more information, see ZBX-24291.
When upgrading Zabbix on Red Hat Enterprise Linux or its derivatives, you may encounter an expired signing key issue for packages on Zabbix repository. When a signing key expires, attempts to verify package signatures will result in an error indicating that the certificate or key is no longer valid. For example:
error: Verifying a signature using certificate D9AA84C2B617479C6E4FCF4D19F2475308EFA7DD (Zabbix LLC (Jul 2022) <[email protected]>):
1. Certificiate 19F2475308EFA7DD invalid: certificate is not alive
because: The primary key is not live
because: Expired on 2024-07-04T11:41:23Z
2. Key 19F2475308EFA7DD invalid: key is not alive
because: The primary key is not live
because: Expired on 2024-07-04T11:41:23Z
To resolve such issues, manually reinstall the latest zabbix-release
package for your specific variant of RHEL (replace the link below with the correct one from Zabbix repository).
For example, on RHEL 9, run:
Then, update the repository information:
For more information, see ZBX-24761.
Database TLS connection is not supported with the 'verify_ca' option for the DBTLSConnect parameter if MariaDB is used.
When running under high load, and with more than one LLD worker involved, it is possible to run into a deadlock caused by an InnoDB error related to the row-locking strategy (see upstream bug). The error has been fixed in MySQL since 8.0.29, but not in MariaDB. For more details, see ZBX-21506.
Events may not get correlated correctly if the time interval between the first and second event is very small, i.e. half a second and less.
PostgreSQL 11 and earlier versions only support floating point value range of approximately -1.34E-154 to 1.34E+154.
Various Zabbix processes may randomly crash on startup on the NetBSD versions 8.X and 9.X. That is due to the too small default stack size (4MB), which must be increased by running:
For more information, please see the related problem report: ZBX-18275.
Zabbix agent 2 does not support lookaheads and lookbehinds in regular expressions due to the standard Go regexp library limitations.
IPMI checks will not work with the standard OpenIPMI library package on Debian prior to 9 (stretch) and Ubuntu prior to 16.04 (xenial). To fix that, recompile OpenIPMI library with OpenSSL enabled as discussed in ZBX-6139.
Some Linux distributions like Debian, Ubuntu do not support encrypted private keys (with passphrase) if the libssh2 library is installed from packages. Please see ZBX-4850 for more details.
When using libssh 0.9.x on some Linux distributions with OpenSSH 8, SSH checks may occasionally report "Cannot read data from SSH server". This is caused by a libssh issue (more detailed report). The error is expected to have been fixed by a stable libssh 0.9.5 release. See also ZBX-17756 for details.
Using the pipe "|" in the SSH script may lead to a "Cannot read data from SSH server" error. In this case it is recommended to upgrade the libssh library version. See also ZBX-21337 for details.
MySQL unixODBC driver should not be used with Zabbix server or Zabbix proxy compiled against MariaDB connector library and vice versa, if possible it is also better to avoid using the same connector as the driver due to an upstream bug. Suggested setup:
PostgreSQL, SQLite or Oracle connector → MariaDB or MySQL unixODBC driver MariaDB connector → MariaDB unixODBC driver MySQL connector → MySQL unixODBC driver
See ZBX-7665 for more information and available workarounds.
XML data queried from Microsoft SQL Server may get truncated in various ways on Linux and UNIX systems.
It has been observed that using ODBC checks for monitoring Oracle databases using various versions of Oracle Instant Client for Linux causes Zabbix server to crash. See also: ZBX-18402, ZBX-20803.
If using FreeTDS UnixODBC driver, you need to prepend a 'SET NOCOUNT ON' statement to an SQL query (for example, SET NOCOUNT ON DECLARE @strsql NVARCHAR(max) SET @strsql = ....
). Otherwise, database monitor item in Zabbix will fail to retrieve the information with an error "SQL query returned empty result".
See ZBX-19917 for more information.
The request method parameter, used only in HTTP checks, may be incorrectly set to '1', a non-default value for all items as a result of upgrade from a pre-4.0 Zabbix version. For details on how to fix this situation, see ZBX-19308.
Zabbix server leaks memory on some Linux distributions due to an upstream bug when "SSL verify peer" is enabled in web scenarios or HTTP agent. Please see ZBX-10486 for more information and available workarounds.
There is a bug in fping versions earlier than v3.10 that mishandles duplicate echo replay packets. This may cause unexpected results for icmpping
, icmppingloss
, icmppingsec
items. It is recommended to use the latest version of fping. Please see ZBX-11726 for more details.
When containers are running in rootless mode or in a specific-restrictions environment, you may face errors related to fping execution when performing ICMP checks, such as fping: Operation not permitted
or all packets to all resources lost.
To fix this problem add --cap-add=net_raw
to "docker run" or "podman run" commands.
Additionally fping execution in non-root environments may require sysctl modification, i.e.:
where "1995" is the zabbix GID. For more details, see ZBX-22833.
If the OpenBSD operating system is used, a use-after-free bug in the Net-SNMP library up to the 5.7.3 version can cause a crash of Zabbix server if the SourceIP parameter is set in the Zabbix server configuration file. As a workaround, please do not set the SourceIP parameter. The same problem applies also for Linux, but it does not cause Zabbix server to stop working. A local patch for the net-snmp package on OpenBSD was applied and will be released with OpenBSD 6.3.
Spikes in SNMP data have been observed that may be related to certain physical factors like voltage spikes in the mains. See ZBX-14318 more details.
The "net-snmp-perl" package, needed for SNMP traps, has been removed in RHEL 8.0-8.2; re-added in RHEL 8.3.
So if you are using RHEL 8.0-8.2, the best solution is to upgrade to RHEL 8.3.
Please also see ZBX-17192 for more information.
Instances of a Zabbix server alerter process crash have been encountered in RHEL 7. Please see ZBX-10461 for details.
When upgrading Zabbix agent 2 (version 6.0.5 or older) from packages, a plugin-related file conflict error may occur. To fix the error, back up your agent 2 configuration (if necessary), uninstall agent 2 and install it anew.
On RHEL-based systems, run:
On Debian-based systems, run:
For more information, see ZBX-23250.
It has been observed that frontend locales may flip without apparent logic, i. e. some pages (or parts of pages) are displayed in one language while other pages (or parts of pages) in a different language. Typically the problem may appear when there are several users, some of whom use one locale, while others use another.
A known workaround to this is to disable multithreading in PHP and Apache.
The problem is related to how setting the locale works in PHP: locale information is maintained per process, not per thread. So in a multi-thread environment, when there are several projects run by same Apache process, it is possible that the locale gets changed in another thread and that changes how data can be processed in the Zabbix thread.
For more information, please see related problem reports:
bcdiv
function of BC Math functions)Changes to Daylight Saving Time (DST) result in irregularities when displaying X axis labels (date duplication, date missing, etc).
When using sum aggregation in a graph for period that is less than one hour, graphs display incorrect (multiplied) values when data come from trends.
For some frontend languages (e.g., Japanese), local fonts can cause text overlapping in graph legend. To avoid this, use version 2.3.0 (or later) of PHP GD extension.
log[]
and logrt[]
items repeatedly reread log file from the beginning if file system is 100% full and the log file is being appended (see ZBX-10884 for more information).
Zabbix server generates slow SELECT
queries in case of non-existing values for items. This issue is known to occur in MySQL 5.6/5.7 versions (for an extended discussion, see ZBX-10652), and, in specific cases, may also occur in later MySQL versions. A workaround to this is disabling the index_condition_pushdown
or prefer_ordering_index
optimizer in MySQL. Note, however, that this workaround may not fix all issues related to slow queries.
Configuration sync might be slow in Zabbix installations with Oracle DB that have high number of items and item preprocessing steps. This is caused by the Oracle database engine speed processing nclob type fields.
To improve performance, you can convert the field types from nclob to nvarchar2 by manually applying the database patch items_nvarchar_prepare.sql. Note that this conversion will reduce the maximum field size limit from 65535 bytes to 4000 bytes for item preprocessing parameters and item parameters such as Description, Script item's field Script, HTTP agent item's fields Request body and Headers, Database monitor item's field SQL query. Queries to determine template names that need to be deleted before applying the patch are provided in the patch as a comment. Alternatively, if MAX_STRING_SIZE is set you can change nvarchar2(4000) to nvarchar2(32767) in the patch queries to set the 32767 bytes field size limit.
For an extended discussion, see ZBX-22363.
A large number of open user sessions can be created when using custom scripts with the user.login
method without a following user.logout
.
Due to a net-snmp bug, IPv6 address may not be correctly displayed when using SNMPv3 in SNMP traps. For more details and a possible workaround, see ZBX-14541.
A failed login attempt message will display only the first 39 characters of a stored IP address as that's the character limit in the database field. That means that IPv6 IP addresses longer than 39 characters will be shown incompletely.
Non-existing DNS entries in a Server
parameter of Zabbix agent configuration file (zabbix_agentd.conf) may increase Zabbix agent response time on Windows. This happens because Windows DNS caching daemon doesn't cache negative responses for IPv4 addresses. However, for IPv6 addresses negative responses are cached, so a possible workaround to this is disabling IPv4 on the host.
There are some known issues with YAML export/import:
Frontend setup wizard cannot save configuration file on SUSE with NGINX + php-fpm. This is caused by a setting in /usr/lib/systemd/system/php-fpm.service unit, which prevents Zabbix from writing to /etc. (introduced in PHP 7.4).
There are two workaround options available:
Though in most cases, Zabbix web service can run with Chromium, on Ubuntu 20.04 using Chromium causes the following error:
Cannot fetch data: chrome failed to start:cmd_run.go:994:
WARNING: cannot create user data directory: cannot create
"/var/lib/zabbix/snap/chromium/1564": mkdir /var/lib/zabbix: permission denied
Sorry, home directories outside of /home are not currently supported. See https://forum.snapcraft.io/t/11209 for details.
This error occurs because /var/lib/zabbix
is used as a home directory of user 'zabbix'.
If Zabbix is used with MySQL installation on Azure, an unclear error message [9002] Some errors occurred may appear in Zabbix logs. This generic error text is sent to Zabbix server or proxy by the database. To get more information about the cause of the error, check Azure logs.
In Zabbix 6.0 support for PCRE2 has been added. Even though PCRE is still supported, Zabbix installation packages for RHEL 7 and newer, SLES (all versions), Debian 9 and newer, Ubuntu 16.04 and newer have been updated to use PCRE2. While providing many benefits, switching to PCRE2 may cause certain existing PCRE regexp patterns becoming invalid or behaving differently. In particular, this affects the pattern ^[\w-\.]. In order to make this regexp valid again without affecting semantics, change the expression to ^[-\w\.] . This happens due to the fact that PCRE2 treats the dash sign as a delimiter, creating a range inside a character class.
The maps in the Geomap widget may not load correctly, if you have upgraded from an older Zabbix version with NGINX and didn't switch to the new NGINX configuration file during the upgrade.
To fix the issue, you can discard the old configuration file, use the configuration file from the current version package and reconfigure it as described in the download instructions in section e. Configure PHP for Zabbix frontend.
Alternatively, you can manually edit an existing NGINX configuration file (typically, /etc/zabbix/nginx.conf). To do so, open the file and locate the following block:
Then, replace this block with:
location ~ /(api\/|conf[^\.]|include|locale) {
deny all;
return 404;
}
location /vendor {
deny all;
return 404;
}
As global variables are shared across different webhook calls, the following code will result in the tag value counter gradually increasing:
try
{
aa = aa + 1;
}
catch(e)
{
aa = 0;
}
result = {
'tags': {
'endpoint': aa
}
};
return JSON.stringify(result);
Using local variables instead of global ones is recommended to make sure that each script operates on its own data and that there are no collisions between simultaneous calls.
Upgrading to Zabbix 7.0.1 (or later) from Zabbix 7.0.0 with PostgreSQL/TimescaleDB results in a server crash. This issue is caused by a workaround to a compression job issue in the auditlog table in Zabbix 7.0 that irreversibly changed the compression policy of the auditlog table.
To fix the issue, please perform a manual rebuild of the auditlog table. The buggy auditlog table can be detected using this query:
SELECT config FROM timescaledb_information.jobs WHERE application_name LIKE 'Compression%' AND hypertable_schema='public' AND hypertable_name='auditlog';.
If it returns a JSON object containing property compress_after
(like {"hypertable_id": 14, "compress_after": 612000}) then you should rebuild the table.
Make sure that Zabbix server is at least 7.0.1rc2 version (or later); otherwise, it will set the wrong compression policy again. Additionally, stop Zabbix server before running the script, and confirm that auditlog
is owned by the zabbix user.
The simplest way for rebuilding the auditlog table is:
CREATE TABLE auditlog_tmp (
LIKE auditlog INCLUDING DEFAULTS INCLUDING CONSTRAINTS INCLUDING INDEXES
);
SELECT create_hypertable('auditlog_tmp', 'auditid', chunk_time_interval => 604800,
time_partitioning_func => 'cuid_timestamp', migrate_data => true, if_not_exists => true);
WITH moved_rows AS (
DELETE FROM auditlog
RETURNING *
)
INSERT INTO auditlog_tmp
SELECT * FROM moved_rows;
DROP TABLE auditlog;
ALTER TABLE auditlog_tmp RENAME TO auditlog;
See also TimescaleDB documentation for more optimized ways to migrate data.
Since the timestamp required for partitioning is extracted from the auditid
field with a custom-made function the helper procedures used for data migration from timescaledb-extras will not work.
Using pg_restore
to restore a PostgreSQL/TimescaleDB backup created in Zabbix 7.0.0-7.0.4 will result in a missing base36_decode
function error, causing the restore to fail:
ERROR: function base36_decode(text) does not exist
LINE 1: CAST(base36_decode(substring(cuid FROM 2 FOR 8))/1000 AS int...
^
HINT: No function matches the given name and argument types. You might need to add explicit type casts.
This error occurs when restoring a backup created with pg_dump
.
To fix this issue, please replace the cuid_timestamp
function in your Zabbix database before creating the backup (stopping PostgreSQL/TimescaleDB before running the script is recommended):
CREATE OR REPLACE FUNCTION cuid_timestamp(cuid varchar(25)) RETURNS integer AS $$
DECLARE
base36 varchar;
a char[];
ret bigint;
i int;
val int;
chars varchar;
BEGIN
base36 := substring(cuid FROM 2 FOR 8);
chars := '0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ';
FOR i IN REVERSE char_length(base36)..1 LOOP
a := a || substring(upper(base36) FROM i FOR 1)::char;
END LOOP;
i := 0;
ret := 0;
WHILE i < (array_length(a, 1)) LOOP
val := position(a[i + 1] IN chars) - 1;
ret := ret + (val * (36 ^ i));
i := i + 1;
END LOOP;
RETURN CAST(ret/1000 AS integer);
END;
$$ LANGUAGE 'plpgsql' IMMUTABLE;
DROP FUNCTION IF EXISTS base36_decode(character varying);
See also ZBX-24955 (for additional details on the error) and TimescaleDB documentation (for additional backup and restore options).