How i fixed it… Im running my zabbix server on ubuntu – Open your sysctl.conf and assign an amount of shared memory #vi /etc/sysctl.conf:  My setting below – 1 kernel.shmmax=2834217728 This gives you 2.6gb of shared space To apply changes in the /etc/sysctl.conf immediately, execute: 1 2 # sysctl -p kernel.shmmax = 2834217728   Now edit Read more about Zabbix: Less than 25% free in the configuration cache[…]