NOTE: The tcp(), tcp6(), udp(), and udp6() drivers are obsolete. Use the network() source and the network() destination instead. For details, see network: Collecting messages using the RFC3164 protocol (network() driver) and network: Sending messages to a remote log server using the RFC3164 protocol (network() driver), respectively.
To convert your existing tcp(), tcp6(), udp(), udp6() source drivers to use the network() driver, see Change an old destination driver to the network() driver.
The tcp(), tcp6(), udp(), and udp6() drivers send messages to another host (for example, a syslog-ng server or relay) on the local intranet or internet using the UDP or TCP protocol. The tcp6() and udp6() drivers use the IPv6 network protocol.