[j-nsp] EX4200 BPDU on access port

Ben Dale bdale at comlinx.com.au
Tue Mar 22 19:09:00 EDT 2011

This is perfectly normal spanning-tree behaviour - if edge ports didn't send BPDUs and you looped a cable between two edge ports then broadcast storm hilarity would ensue.

If you want to stop this from occurring (and have a good understanding of the implications of doing this between two switches), disable RSTP on the interface:

set protocols rstp interface ge-0/0/0 disable

If you're just trying to keep your RSTP topology separate but want to keep the protection mechanisms in place, use root-guard:

set protocols rstp interface ge-0/0/0.0 mode point-to-point
set protocols rstp interface ge-0/0/0.0 no-root-port

If you're carrying traffic for your customer from one site to another (Q-in-Q) and they need their spanning-tree topology maintained transparently across your network, then you'll need to use dot1q-tunneling:

set vlans CUST-A-OUTER dot1q-tunneling layer2-protocol-tunneling stp
set vlans CUST-A-OUTER dot1q-tunneling layer2-protocol-tunneling vstp

On 23/03/2011, at 8:10 AM, Pavel Dimow wrote:

> Hi,
> I have strange situation where my customer receives bpdu's on his
> cisco switch from my ex4200 despite the fact that I have configured my
> port as access (default in JUNOS)
> and as edge on rstp configuration. Is this normal or I don't have luck
> with 10.3 version?
> _______________________________________________
> juniper-nsp mailing list juniper-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/juniper-nsp

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