The most frequent cause is the Zabbix user hitting the Linux "Open Files" limit. When Zabbix cannot open new file descriptors for internal communication, it drops connections, resulting in a "Broken pipe."
Zabbix agent [active] or server: cannot write to IPC socket: [32] Broken pipe zabbix cannot write to ipc socket broken pipe upd
Memory limits, timeouts, or missing dependencies can kill the process, breaking the pipe. The most frequent cause is the Zabbix user
