Vlan – STP Packet on specific interface eth1

spanning treevlan

I have an issue related to some stp packet that being sent every 1 or 2 second on my server interface eth1.
This interface is connected to my stack switch, and the port is in a public vlan.
Here is the output I have from the server:

server-1:
user@server-1:~$ sudo tcpdump -vvv -p -n -i eth1 stp
tcpdump: listening on eth1, link-type EN10MB (Ethernet), capture size 65535 bytes

15:44:10.772423 STP 802.1d, Config, Flags [none], bridge-id  8000.MAC.8687, length 43
        message-age 0.00s, max-age 20.00s, hello-time 2.00s, forwarding-delay 15.00s
        root-id 8000.MAC, root-pathcost 0
15:44:12.768245 STP 802.1d, Config, Flags [none], bridge-id 8000.MAC8.8687, length 43
        message-age 0.00s, max-age 20.00s, hello-time 2.00s, forwarding-delay 15.00s
        root-id 8000.MAC, root-pathcost 0
15:44:14.766513 STP 802.1d, Config, Flags [none], bridge-id 8000.MAC.8687, length 43
        message-age 0.00s, max-age 20.00s, hello-time 2.00s, forwarding-delay 15.00s
        root-id 8000.MAC, root-pathcost 0
15:44:16.766478 STP 802.1d, Config, Flags [none], bridge-id 8000.MAC.8687, length 43
        message-age 0.00s, max-age 20.00s, hello-time 2.00s, forwarding-delay 15.00s
        root-id 8000.MAC, root-pathcost 0
15:44:18.767851 STP 802.1d, Config, Flags [none], bridge-id 8000.MAC.8687, length 43
        message-age 0.00s, max-age 20.00s, hello-time 2.00s, forwarding-delay 15.00s
        root-id 8000.MAC, root-pathcost 0
---------------------------------------------------------------------

Do anyone know what is the issue here!? I did a research over the Internet but all queries on this topic is never ended or there is no answer.

Any help is welcome.

Thank you for your time.

Best Answer

This are just spanning tree packets from your switch. Disable spanning tree on your switch on the interface towards your server if you don't need it and don't want to see these packets.

Related Solutions

STP load balancing

For lack of a question, I'll assume the following.

Is this working the way I intend on making it work?

Unfortunately, it's not. Spanning-tree has selected Gi0/24 on each port because it's a lower root path cost, so it isn't taking the spanning-tree port-priority into account. When STP making it's calculations, it follows these orders.

Root Bridge Identifier, the Bridge Identifier of the Bridge believed to be the Root by the transmitter

Root Path Cost, to that Root Bridge from the transmitting Bridge

Bridge Identifier, of the transmitting Bridge

Port Identifier, of the Port through which the message was transmitted

Port Identifier, of the Port through which the message was received (where relevant)

^{Info derived from IEEE Standard 802.1D - 2004, Media Access Control (MAC) Bridges, section 17.5 Spanning tree priority vectors}

Since Gi0/23 is connected to a FastEthernet port, it inherently has a lower speed (resulting in a higher cost).

     Interface           Role Sts Cost      Prio.Nbr Type
     Gi0/23              Altn BLK 19        128.23   P2p
     Gi0/24              Root FWD 4         128.24   P2p
                                  ^^^

If you want to load balance across these links with STP, you would also need to add the following configurations:

interface GigabitEthernet0/24
 spanning-tree vlan 70,80,90,100,150 cost 4
interface GigabitEthernet0/23
 spanning-tree vlan 10,20,30,40,50,60 cost 4

When is stp disable

This looks like comeware like in 3com or some HP branded (1900s and the enterprise 5000s)

The reason some people disable STP is to use it as an edge port. The reason for an edge port ...

When using standard STP with the fast computers of today a computer can boot and request DHCP before STP converges and allows the port to communicate. When this happens a computer doesn't get an ip address and it can't communicate.

Some other info:

Rapid spanning tree helps some of this issue by converging faster.

Cisco portfast will let the port come up first then check for loops.

Disabling STP per port turns it off completely off course.

I personally leave spanning tree on as often as possible. I've seen people plug loops in places you'd never guess!

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