Description: Select only messages sent by a host whose IP address belongs to the specified IPv4 subnet. Note that this filter checks the IP address of the last-hop relay (the host that actually sent the message to syslog-ng PE), not the contents of the HOST field of the message. You can use both the dot-decimal and the CIDR notation to specify the netmask. For example, 192.168.5.0/255.255.255.0 or 192.168.5.0/24. To filter IPv6 addresses, see netmask6().