Hello  Theo_C3,

I will have to look into this.

 Could you post your running-config for us to get a look?

Please delete personal information like serial number/ service tag before posting.

You may try switchport protected. Traffic from protected ports is sent only to the uplink ports and cannot be sent to other ports within the VLAN.

page 464 here: https://dell.to/3rCaRU7

Hello Charles R,

Thank you for your answer, indeed, changing the ports to protected mode could be a solution. But in case I need two protected ports to communicate with each other, is there a command for that? 

For example, I would like a host1 to be able to communicate only with another host2 and not the other hosts.

Thank you,
Theo.

Hi, if you check pg 901, I don't think they can communicate with each other. Because protected ports can communicate only with unprotected ports. https://dell.to/3fPoNrg quoted "The switch supports up to three separate groups of protected ports. Traffic
can flow between protected ports belonging to different groups, but not
within the same group.
A port can belong to only one protected port group. You must remove an
interface from one group before adding it to another group.
Port protection occurs within a single switch. Protected port configuration
does not affect traffic between ports on two different switches. No traffic
forwarding is possible between two protected ports.
When an interface is enabled for routing (via the interface vlan command),
the port will no longer be operationally enabled as a protected port on the
interface. If the interface is part of a LAG or is a probe port, the feature is
disabled for the port. "