Add documentation for fastdds.shm.only_host_id_on_locators

docs/docker/shm_docker.rst

@@ -27,6 +27,12 @@ command, those are:
   A more advanced user could set the flag to `shared`, thus sharing the shared memory mechanism of one of the container
   with the others.
 
+Starting with Fast DDS Pro 3.7.0, the participant property ``fastdds.shm.only_host_id_on_locators`` shall also be set
+to ``true`` to force the SHM transport to not consider the machine ID on the locators, since the machine ID would
+probably be different for each container, and therefore the SHM transport would not be able to find the other
+participants.
+See :ref:`property_policies_shm_host_id_only` for more information.
+
 .. code-block:: bash
 
    docker run -it --rm --network=host --ipc=host [OPTIONS] <docker-image>

docs/fastdds/property_policies/non_consolidated_qos.rst

@@ -348,6 +348,30 @@ The behavior regarding this can be configured using the property ``fastdds.shm.e
         :start-after: <!-->XML-SHM-ENFORCE-META-TRAFFIC
         :end-before: <!--><-->
 
+.. _property_policies_shm_host_id_only:
+
+SHM transport locators format |Pro|
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+Prior to version 3.7.0 of *Fast DDS*, the locators format for SHM transport included a two byte ID
+based on the IP addresses of the host, which was used to identify the host in which the participant
+was running.
+Starting from version 3.7.0, the locators format for SHM transport has been changed to also include
+a 13-byte ID based on the machine ID of the host.
+
+When the machine ID part of the locator is set, it is used to identify the host in which a
+participant is running, and the IP-based host ID part of the locator is ignored.
+When the machine ID part of the locator is not set, the IP-based host ID part of the locator is
+used to identify the host in which a participant is running.
+
+In certain scenarios, where virtual machines are cloned or containers are created from the same
+image, the machine ID of the host may be the same for different hosts, which may lead to
+participants running in different hosts being considered to be running in the same host, and
+therefore not being able to communicate.
+In order to avoid this situation, the property ``fastdds.shm.only_host_id_on_locators`` can be set
+to ``true`` to force the SHM transport to use only the IP-based host ID part of the locator, both
+in the announced locators and when processing the locators of remote participants.
+
 .. _property_max_message_size:
 
 Maximum Message Size