Thx chenhui,
now it's clear, the allowed-pass command used in trunk ports is splitted in port hybrid tagged/untagged commands in
order to enable vlans inbound/outbound.
In think hybrid port is the most powerful: can reproduce the exact behavior of a trunk port and access port.
Trunk port is only able to reproduce the exact behavior of an access port.
There are cases like Selective QinQ that could be accomplished only with the power of a hibryd port.
Now it's clear to me why hybrid ports are the default on Huawei switches, with them you can have all possible port functionalities.
Anyway, for the sake of cleanness I think it's convenient to choose the link-type that satisfy my requirements (access for hosts, trunk for switch upstream), reserving the use of hybrid ports to special cases.
