Switch stack ring and uplinks

I really enjoy discussing network design and deploy details with colleagues, customers and fellow network engineer. I find these discussions challenging, stimulating. An open, sincere and collaborative discussion gives a chance to better understand the real needs, fears, doubts of other professionals and to validate knowledge, expose gaps and most of all I learn a lot. This is still valid when discussing Data Center design or simpler topics like how to cable switch stacks.

L2 QoS lab with DSCP mutation map and QoS port statistics

The dscp mutation map is a per-port configuration that permits to modify the dscp field of a packet. The mutation map works for EGRESS traffic only We trust the documentation but it’s event better to verify it. The topology si simple: PC1 -- G1/0/1 C3750-24 G1/0/24 -- G1/0/24 C3750-48 G1/0/1 -- PC2 running wireshark First step: turn on QOS on both switches with the command mls qos Then on C3750-24 port G1/0/1 we set COS to 5:

PVLAN Quick Notes

Private VLAN configuration: vlan 300 private-vlan primary private-vlan association 301-302 ! vlan 301 private-vlan isolated ! vlan 302 private-vlan community Port configuration: interface GigabitEthernet1/0/1 switchport private-vlan host-association 300 301 switchport mode private-vlan host What about the SVI? interface Vlan300 ip address private-vlan mapping ? WORD Secondary VLAN IDs of the private VLAN SVI interface mapping add Add a VLAN to private VLAN list remove Remove a VLAN from private VLAN list If we add a private-vlan mapping to the SVI it works like a promicuous port for all the secondary vlans mapped, reachable by both isolated and community ports: