You can display network traffic statistics per VLAN using the vlan-stats-show command. This may be useful when troubleshooting network issues.
CLI network-admin@Leaf1 > vlan-stats-show format all layout vertical
The output displays the following information:
switch — switch name
time — when the output was generated
VLAN ID — ID assigned to the VLAN
vnet — the VNET assigned to the VLAN
incoming and outgoing bytes — in K (Kilobytes), M (Megabytes), or G (Gigabytes)
incoming and outgoing packets — number of packets incoming and outgoing
incoming and outgoing dropped bytes — in K (Kilobytes), M (Megabytes), or G (Gigabytes)
incoming and outgoing dropped packets — number of dropped packets incoming and outgoing
Rapid Spanning Tree Protocol (RSTP) is a standard inter-switch protocol to ensure that an ad hoc network topology is loop-free at Layer 2, on a per-VLAN basis. If your network connections form loops and STP is disabled, packets re-circulate between the switches, causing a degradation of network performance. If you are certain that your network connections are loop-free, you do not need to enable RSTP. A drawback of STP is that it does not allow for Layer 2 multipathing and can result in sub-optimal utilization of available network links. Therefore, a fabric of switches does not run RSTP within the boundaries of the fabric. The use of RSTP is recommended for ad hoc networks that interoperate in a heterogeneous, multi-vendor switch environment.
To build a loop-free topology, switches (“bridges”) have to determine the root bridge and compute the port roles, root, designated, or blocked. To do this, the bridges use special data frames called Bridge Protocol Data Units (BPDUs) to exchange information about bridge IDs and root path costs. BPDUs are exchanged regularly, typically at two second intervals, and enable switches to keep track of network topology changes and to start and stop forwarding on ports as required. Hosts should not send BPDUs to their switch ports and to avoid malfunctioning or malicious hosts from doing so, the switch can filter or block BPDUs. If you enable BPDU filtering on a port, BPDUs received on that port are dropped but other traffic is forwarded as usual. If you enable BPDU blocking on a port, BPDUs received on that port are dropped and the port is shut down.
Rapid Spanning Tree Protocol is also supported by modifying an RSTP port and configuring it as an edge port.
Informational Note: RSTP is enabled on the switch by default.
Before you begin, view the status of STP on the switch by using the following command:
CLI network-admin@Leaf1 > stp-show
1. To disable STP, use the following command:
CLI network-admin@Leaf1 > stp-modify disable
To display the STP state, use the following command:
CLI network-admin@Leaf1 > stp-state-show
To display information about STP on ports, use the stp-port-show command:
CLI network-admin@Leaf1 > stp-port-show
switch port block filter edge bpdu-guard root-guard priority cost
-------- ---- ----- ------ ---- ---------- ---------- -------- ----
draco01 1 off off no no no 128 500
draco01 2 off off no no no 128 2000
draco01 3 off off no no no 128 2000
draco01 4 off off no no no 128 2000
draco01 5 off off no no no 128 500
draco01 6 off off no no no 128 500
draco01 7 off off no no no 128 2000
draco01 8 off off no no no 128 2000
draco01 9 off off no no no 128 2000
draco01 10 off off no no no 128 500
To filter BPDUs on port 17, use the following command:
CLI network-admin@Leaf1 > stp-port-modify port 17 filter
To block BPDUs on port 17 and shut down the port if BPDUs are received on the port, use the following command:
CLI network-admin@Leaf1 > stp-port-modify port 17 block
To stop blocking BPDUs on port 17, use the following command:
CLI network-admin@Leaf1 > stp-port-modify port 17 no-block
You can disable STP on a port or a group of ports. If the devices connected to the switch ports are hosts and not downstream switches, or you know that a loop is not possible, then disable STP and the port is enabled much faster when the switch restarts.
To enable RSTP on port 35, use the following command:
CLI network-admin@Leaf1 > stp-port-modify port 35 edge
To enable STP, use the following command:
CLI network-admin@Leaf1 > stp-modify enable
Managing STP BPDU After Disabling LLDP
Netvisor ONE optimizes STP BPDUs by not sending BPDUs on any ports if the ports are not switch ports. This is the default setting for the parameter, bpdus-bridge-port. If you do not configure LLDP, Netvisor One does not detect host ports and does not t send BPDU pacekts. As a result, both ports are in Forwarding state.
When you add the parameter, bpdus-all-ports, to allow sending BPDUs on ports even if ports are not detected, unless the port is configured as an edge port. On a switch with a port connected to itself with this configuration one of the ports goes into a Discarding state.