# 8 Known issues #### Problems with pressing Enter in configuration forms Affects Zabbix 3.2.0. Pressing Enter in a text field of a configuration form is known to result in various problems. For instance, if you open the configuration form of a host with linked templates, then press Enter in any text field and update the form, template linkage is removed (items from the template remain). #### 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](https://support.zabbix.com/browse/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](https://support.zabbix.com/browse/ZBX-4850) for more details. #### ODBC checks Zabbix server or proxy that uses MySQL as its database may or may not work correctly with MySQL ODBC library due to an [upstream bug](https://bugs.mysql.com/bug.php?id=73709). Please see [ZBX-7665](https://support.zabbix.com/browse/ZBX-7665) for more information and available workarounds. XML data queried from Microsoft SQL Server may get truncated to 2033 characters due to a Microsoft [issue](https://support.microsoft.com/en-us/help/310378/the-xml-data-row-is-truncated-at-2-033-characters-when-you-use-the-sql). #### HTTPS checks Web scenarios using the https protocol and Zabbix agent checks `net.tcp.service[https...]` and `net.tcp.service.perf[https...]` may fail if the target server is configured to disallow TLS v1.0 protocol or below. Please see [ZBX-9879](https://support.zabbix.com/browse/ZBX-9879) 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](https://support.zabbix.com/browse/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. #### 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](https://support.zabbix.com/browse/ZBX-10461) for details. #### Web monitoring Zabbix server leaks memory on CentOS 6, CentOS 7 and possibly other related Linux distributions due to an [upstream bug](https://bugzilla.redhat.com/show_bug.cgi?id=1057388) when "SSL verify peer" is enabled in web scenarios. Please see [ZBX-10486](https://support.zabbix.com/browse/ZBX-10486) for more information and available workarounds. #### 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. #### 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](https://support.zabbix.com/browse/ZBX-10884) for more information). #### Macro functions When **\\0** is used as the output option in [macro functions](/manual/config/macros/macro_functions) it will work as designed, i.e. return the matched text, when server does the resolving (in trigger tags, notification messages), but **not** in cases when frontend does the resolving. #### Slow MySQL queries Zabbix server generates slow select queries in case of non-existing values for items. This is caused by a known [issue](https://bugs.mysql.com/bug.php?id=74602) 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](https://support.zabbix.com/browse/ZBX-10652). #### API fails decoding valid JSON-RPC request Affects Zabbix versions 3.2.0, 3.2.1. API fails to decode a valid JSON-RPC request unless a non-requirement php-json module is installed. [ZBX-11244](https://support.zabbix.com/browse/ZBX-11244) contains more information on this issue. #### Escalations Several operations can be assigned to the same step. If these operations have different step duration defined, the shortest one is taken into account and applied to the step. But due to bug there was exception to this rule when step duration is set to 0, it would use default value instead of shortest one. Now there will be no exception and default step duration will only be used if it's shortest, this is equivalent to behavior that frontend shows and user expects. Affects all versions, fixed in 3.2.3rc1, (see [ZBX-11534](https://support.zabbix.com/browse/ZBX-11534) for more information). #### Time-based functions ignored in recovery expressions Affects Zabbix versions 3.2.0 - 3.2.4. Triggers with time-based functions in the recovery expression only are not periodically recalculated by the timer process. #### API The **output** parameter does not work properly with the `history.get` method. #### API login A large number of open user sessions can be created when using custom scripts with the `user.login` [method](/manual/api/reference/user/login) without a following `user.logout`.