Onload and IP_MULTICAST_TTL

Onload User Guide (UG1586)

Document ID
UG1586
Release Date
2023-07-31
Revision
1.2 English

Onload will act in accordance with RFC 791 when it comes to the IP_MULTICAST_TTL setting. Using Onload, if IP_MULTICAST_TTL=0, packets will never be transmitted on the wire.

This differs from the Linux kernel where the following behavior has been observed:

Kernel - IP_MULTICAST_TTL 0 - if there is a local listener, packets will not be transmitted on the wire.

Kernel - IP_MULTICAST_TTL 0 - if there is NO local listener, packets will always be transmitted on the wire.