zabbix_proxy on MySQL versions 8.0.0-8.0.17 fails with the following "access denied" error:
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
For MySQL versions 8.0.14 - 8.0.17:
For MySQL versions 8.0.0 - 8.0.13:
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).
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.
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.
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 CentOS 8 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.
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 CentOS 6, CentOS 7 and possibly other related 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
icmppingsec items. It is recommended to use the latest version of fping. Please see ZBX-11726 for more details.
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/CentOS 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; if you are using CentOS 8.0-8.2, you may wait for CentOS 8.3 or use a package from EPEL.
Please also see ZBX-17192 for more information.
Instances of a Zabbix server alerter process crash have been encountered in Centos/RHEL 7. Please see ZBX-10461 for details.
If you install the PCRE library from a popular HP-UX package site http://hpux.connect.org.uk, for example from file
pcre-8.42-ia64_64-11.31.depot, you get only the 64-bit version of the library installed in the /usr/local/lib/hpux64 directory.
In this case, for successful agent compilation customized options need to be used for the "configure" script, e.g.:
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:
bcdivfunction of BC Math functions)
It has been observed that with PHP 7.0 importing a template with web monitoring triggers may fail due to incorrectly added double quotes to the web monitoring items in the trigger expressions. The issue goes away when upgrading PHP to 7.1.
If "opcache" is enabled in the PHP 7.3 configuration, Zabbix frontend may show a blank screen when loaded for the first time. This is a registered PHP bug. To work around this, please set the "opcache.optimization_level" parameter to
0x7FFFBFDF in the PHP configuration (php.ini file).
Changes to Daylight Saving Time (DST) result in irregularities when displaying X axis labels (date duplication, date missing, etc).
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 is caused by a known issue in MySQL 5.6/5.7 versions. A workaround to this is disabling the index_condition_pushdown optimizer in MySQL. For an extended discussion, see ZBX-10652.
Prior to MariaDB 10.2.26, 10.3.17, and 10.4.7, MariaDB didn't properly calculate the row sizes while executing DDL, so "unsafe" tables could be created, even with
innodb_strict_mode=ON set. This was fixed by MDEV-19292. As a side effect, tables that could be created in previous versions may get rejected after the latest releases.
Suggested database changes for existing 4.0 installations:
Suggested database changes for new 4.0 installations:
Perform database creation as usual and fix schema after:
shell> mysql -uroot -p<password> mysql> alter table `host_inventory` modify `name` varchar(128) default '' not null, modify `alias` varchar(128) default '' not null, modify `os` varchar(128) default '' not null, modify `os_short` varchar(128) default '' not null; mysql> set global innodb_strict_mode='ON';
The output parameter does not work properly with the
history.get method (fixed in 4.0.11).
A large number of open user sessions can be created when using custom scripts with the
user.login method without a following
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.
Maps, in Internet Explorer 11, are cut off on the right side if the map content is larger than the dashboard widget area (instead of being resized proportionately). This is intentional because of an IE11-related issue with proper resizing of SVG images.
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.
If Zabbix is used with MySQL installation on Azure, an unclear error message  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.
/zabbix.php?action=dashboard.view&fullscreen=1. Fixed in 4.0.1.
net.dnsZabbix agent item does not support IPv6 addresses in its first parameter. Fixed in 4.0.6.
Zabbix 4.0 installations with MySQL 5.X and 8.0.19 might run a slow query when retrieving problem/event information from the database. In particular, this affects the Problems by severity widget,
problem.get API methods. To improve performance of SQL statements, apply the patch provided in ZBX-18080 (available for Zabbix 4.0.26 and newer).
assetsdirectory for the web server user. This requirement, however, would break those installations of the frontend where the web server has no write permissions to the document root (see ZBX-16180 for details). As a result, this requirement is rolled back in 4.0.9.