Comment 1 for bug 1888282

For future research, 30 seconds is pretty fast if the cloud is busy.

exception oslo_messaging.MessagingTimeout [0]
    Raised if message sending times out.

default_send_timeout [1]
    Type
        integer
    Default
        30
    Minimum Value
        5
    The deadline for an rpc cast or call message delivery. Only used when caller does not provide a timeout expiry.

[0] https://docs.openstack.org/oslo.messaging/ocata/exceptions.html
[1] https://docs.openstack.org/oslo.messaging/rocky/configuration/opts.html#oslo-messaging-rabbit