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listen sets the UDP port Nebula will use for sending/receiving traffic and for handshakes.

port: 4242
batch: 64
read_buffer: 10485760
write_buffer: 10485760


host is the ip of the interface to use when binding the listener. The default is for all IPv4 interfaces. To enable IPv6, use '[::]' instead. host may also contain a hostname.


port is the UDP port nebula should use on a host. For a lighthouse node, the port should be defined, conventionally to 4242, however using port 0 or leaving port unset will dynamically assign a port and is recommended for roaming nodes. Using 0 on lighthouses and relay hosts will likely lead to connectivity issues.


Default: 64

Sets the max number of packets to pull from the kernel for each syscall (under systems that support recvmmsg).

listen.read_buffer, listen.write_buffer

Configure socket buffers for the udp side (outside), leave unset to use the system defaults. Values will be doubled by the kernel. Default is net.core.rmem_default and net.core.wmem_default (/proc/sys/net/core/rmem_default and /proc/sys/net/core/rmem_default). Maximum is limited by memory in the system, SO_RCVBUFFORCE and SO_SNDBUFFORCE is used to avoid having to raise the system wide max, net.core.rmem_max and net.core.wmem_max