IP range setting is not correct

[chris-joys]

I do some test on this plugin. Using rabbitmq 3.8.8 with erlang 21.3

Following is my IP:
IPv4 Address. . . . . . . . . . . : 10.196.33.53
Subnet Mask . . . . . . . . . . . : 255.255.254.0
Default Gateway . . . . . . . . . : 10.196.32.1

I set following content in the advanced.config:
[
{rabbit, [
{tcp_listeners, [5672]},
{auth_backends, [
{rabbit_auth_backend_internal,
[rabbit_auth_backend_internal, rabbit_auth_backend_ip_range]
}
]
}
]},
{rabbitmq_auth_backend_ip_range, [
{tag_masks,
[{'ip-private', [<<"::FFFF:10.196.33.100/114">>]}]},
{default_masks, [<<"::0/0">>]}
]}
].

user is tester1 with the ip-private tag.
I think i should not able to check the exchanges. but actrully i can check it in my computer.

then i change the line to [{'ip-private', [<<"::FFFF:10.196.33.100/220">>]}]
I can't get the exchange information now.

I really don't know how the "::FFFF:10.196.33.100/220" works.
Why 100/114 will not block my IP and 100/220 block it? I think all of them should block my IP.

[chris-joys]

and i also tried following configure:
[{'ip-private', [<<"::FFFF:10.196.33.53/255">>]}]}
i think i will get exchange info, but not.

then i changed it to:
[{'ip-private', [<<"::FFFF:10.196.33.53/114">>]}]}
i can get the exchange:

I found all the numbers bigger than 114 will block the exchanges table display. and the numbers lower than 114 will show this table.
what's the definition of this number?

Thanks!