- 7 Known issues
- Proxy startup with MySQL 8.0.0-8.0.17
- Upgrade with MariaDB 10.2.1 and before
- NetBSD 8.0 and newer
- Global event correlation
- IPMI checks
- SSH checks
- ODBC checks
- Incorrect request method parameter in items
- Web monitoring and HTTP agent
- Simple checks
- SNMP checks
- SNMP data spikes
- SNMP traps
- Alerter process crash in Centos/RHEL 7
- Compiling Zabbix agent on HP-UX
- Flipping frontend locales
- Compatibility issue with PHP 7.0
- PHP 7.3 opcache configuration
- Graphs
- Log file monitoring
- Slow MySQL queries
- MariaDB row size error
- API
- API login
- IPv6 address issue in SNMPv3 traps
- IE11 issue with map resizing in dashboard widgets
- Zabbix agent checks on Windows
- MySQL custom error codes
- Known issues in 4.0.0
- Known issues in 4.0.0, 4.0.1
- Known issues in 4.0.0 - 4.0.2
- Known issues in 4.0.2
- Known issues in 4.0.0 - 4.0.3
- Known issues in 4.0.3
- Known issues starting with 4.0.3
- Known issues in 4.0.0 - 4.0.5
- Known issues in 4.0.6, 4.0.7
- Known issues in 4.0.8
- Known issues in 4.0.0 - 4.0.15
7 Known issues
Proxy startup with MySQL 8.0.0-8.0.17
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:
grant SESSION_VARIABLES_ADMIN on *.* to 'zabbix'@'localhost';
For MySQL versions 8.0.0 - 8.0.13:
grant SYSTEM_VARIABLES_ADMIN on *.* to 'zabbix'@'localhost';
Upgrade with MariaDB 10.2.1 and before
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).
NetBSD 8.0 and newer
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:
ulimit -s 10240
For more information, please see the related problem report: ZBX-18275.
Global event correlation
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
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.
SSH checks
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.
ODBC checks
- 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
Please 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 on CentOS 8 for monitoring Oracle databases using Oracle Instant Client for Linux 11.2.0.4.0 causes the Zabbix server to crash. The issue can be solved by upgrading Oracle Instant Client to 12.1.0.2.0, 12.2.0.1.0, 18.5.0.0.0 or 19. See also ZBX-18402.
Incorrect request method parameter in items
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.
Web monitoring and HTTP agent
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.
Simple checks
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.
SNMP checks
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.
SNMP data spikes
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.
SNMP traps
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.
Alerter process crash in Centos/RHEL 7
Instances of a Zabbix server alerter process crash have been encountered in Centos/RHEL 7. Please see ZBX-10461 for details.
Compiling Zabbix agent on HP-UX
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.:
CFLAGS="+DD64" ./configure --enable-agent --with-libpcre-include=/usr/local/include --with-libpcre-lib=/usr/local/lib/hpux64
Flipping frontend locales
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:
- ZBX-10911 (Problem with flipping frontend locales)
- ZBX-16297 (Problem
with number processing in graphs using the
bcdivfunction of BC Math functions)
Compatibility issue with PHP 7.0
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.
PHP 7.3 opcache configuration
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).
Graphs
Changes to Daylight Saving Time (DST) result in irregularities when displaying X axis labels (date duplication, date missing, etc).
Log file monitoring
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).
Slow MySQL queries
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.
MariaDB row size error
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:
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;
Suggested database changes for new 4.0 installations:
shell> mysql -uroot -p<password>
mysql> set global innodb_strict_mode='OFF';
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';
API
The output parameter does not work properly with the history.get
method (fixed in 4.0.11).
API login
A large number of open user sessions can be created when using custom
scripts with the user.login method
without a following user.logout.
IPv6 address issue in SNMPv3 traps
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.
IE11 issue with map resizing in dashboard widgets
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.
Zabbix agent checks on Windows
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.
MySQL custom error codes
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.
Known issues in 4.0.0
- Fullscreen mode for the dashboards cannot be accessed with the
respective URL parameter:
/zabbix.php?action=dashboard.view&fullscreen=1. Fixed in 4.0.1. - When filtering triggers in Monitoring → Overview (Triggers), trigger severity instead of problem severity is taken into account.
Known issues in 4.0.0, 4.0.1
- Upgrade to 4.0.0 and 4.0.1 from Zabbix 3.0 does not replace {TRIGGER.NAME} macros to {EVENT.NAME} macros like it should. Fixed for 4.0.2.
Known issues in 4.0.0 - 4.0.2
- If the Check now request is performed from the item list for items that do not support it (template items, active agent items, etc.), a 'Request sent successfully' message is displayed even though the functionality does not work for these items. Fixed in 4.0.3, by displaying a corresponding error message.
Known issues in 4.0.2
- Parent host group selection does not work in the following
locations:
- Monitoring → Problems filter
- Monitoring → Dashboard widgets with host group selection:
- Reports → Triggers top 100 filter
Known issues in 4.0.0 - 4.0.3
- Time suffixes do not work in constants of calculated item formulas. Fixed in 4.0.4.
- Negative problem duration affects the total result in SLA calculation or Availability report, making it incorrect. Fixed in 4.0.4.
Known issues in 4.0.3
- If an item is deleted that has a low-level discovery created trigger, the trigger is not deleted. This leads to "orphaned" problems (with no item/host) being displayed in the problem view. Similarly, if an item is deleted that has low-level discovery created dependent item, the dependent item is not deleted. Fixed in 4.0.4.
Known issues starting with 4.0.3
- Failed login attempt message has been changed to 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.
Known issues in 4.0.0 - 4.0.5
net.dns[]Zabbix agent item does not support IPv6 addresses in its first parameter. Fixed in 4.0.6.
Slow event info retrieval with older MySQL databases
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, event.get and 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).
Known issues in 4.0.6, 4.0.7
- IPMI pollers are unable to process more than 60 items per minute. Fixed in 4.0.8.
- You may encounter the issue of 100% CPU usage by IPMI pollers if using OpenIPMI version 2.0.26 and above. Fixed in 4.0.8.
Known issues in 4.0.8
- This version requires write permissions to the
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.
Known issues in 4.0.0 - 4.0.15
- High memory usage has been observed during process startup with SQLite 3.7.17 on Centos/RHEL 7. The startup process has been improved in 4.0.16 to avoid similar issues with other databases as well. See ZBX-9084 for more details.