Release Notes for Zabbix 6.4.21rc1

20 January 2025

Zabbix Team is pleased to announce the availability of Zabbix 6.4.21rc1.

Zabbix is an enterprise-class open source distributed monitoring solution. Zabbix is released under the GPL, thus it is free of charge for both commercial and non-commercial use. A complete text of the license is available at http://www.gnu.org/copyleft/gpl.txt.

This document contains the release notes for Zabbix 6.4.21rc1. Download here.

The following sections describe the release in details and provide late-breaking or other information that supplements its main documentation.

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Bug Fixes

ZBX-25865	Fixed issue causing vmware.hv.network.linkspeed metric failure and resulting in poller becoming unresponsive Proxy Server
ZBX-25732	Fixed inability to make cross-origin requests to API when passing authentication token using Authorization HTTP header; fixed inability to make cross-origin HTTP OPTIONS request to API endpoint API
ZBX-24692	Fixed crash during invalid JSONPath preprocessing Proxy Server
ZBX-24895	Changed double quotes to single quotes for a string in an SQL statement Frontend
ZBX-25377	Fixed crash when executing vfs.fs.size or other metrics and forked metric is terminated abnormally Agent

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Installation and Upgrade Notes

Installation

See Zabbix documentation for full details.

Upgrade

See Upgrade procedure for upgrade options and instructions. For version specific upgrade notes, see Upgrade notes for 6.4.21.

Commercial support

Zabbix Company provides a full range of Professional Services. We also provide trouble-free Upgrade Service for easy migration from earlier versions of Zabbix. Please Contact sales for pricing and more details.

• Zabbix Enterprise Support
• Zabbix Training
• Zabbix Development services

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References

Zabbix 6.4 Manual