RSTP is not working as expected HP2824

[Stefan Priebe]

Hello,

my network is looking like this:

Switch 1 RSTP
Port 24 + Prio 112 => Router 1 / Root Port
Port 23 + Prio 96 => Switch 2
Port 2 + Prio 128 => Rack 2 HP 2610
Port 1 + Prio 128 => Rack 1 HP 2610

Switch 2 RSTP
Port 24 + Prio 112 => Router 2
Port 23 + Prio 96 => Switch 1 / Root Port
Port 2 + Prio 144 => Rack 2 HP 2610
Port 1 + Prio 144 => Rack 1 HP 2610

Now when i pull the cable to port 2 switch 2. Everything is OK no downtime. But when i put it in again i have a network downtime of 5 seconds and a downtime of Rack 2 for about 20 seconds.

Is this correct? Any idea why this happens`?

Thanks for your answer.

Stefan

[Richard Brodie_1]

Could you attach the output of "show span" for Switch 1 and Switch2 ?

The two rack switches (2610s) they have spanning tree disabled?

[Stefan Priebe]

Thanks for your answer.

>Could you attach the output of "show span"
> for Switch 1 and Switch2 ?
No Problem. Here it comes:
Rapid Spanning Tree (RSTP) Information

STP Enabled : Yes
Force Version : RSTP-operation

Switch Priority : 12288 Hello Time : 2
Max Age : 20 Forward Delay : 15

Topology Change Count : 390
Time Since Last Change : 33 hours

Root MAC Address : 000480-789503
Root Path Cost : 20000
Root Port : 24
Root Priority : 0

Root Guard Ports :
TCN Guard Ports :
BPDU Protected Ports :
BPDU Filtered Ports :

Port Type Cost Priority State | Designated Bridge
----- --------- --------- -------- ---------- + -----------------
1 100/1000T 200000 128 Forwarding | 000e7f-6e6a60
2 100/1000T 200000 128 Forwarding | 000e7f-6e6a60
3 100/1000T 200000 128 Forwarding | 000e7f-6e6a60
4 100/1000T 20000 128 Forwarding | 000e7f-6e6a60
5 100/1000T 20000 128 Disabled |
6 100/1000T 20000 128 Forwarding | 000e7f-6e6a60
7 100/1000T 200000 128 Forwarding | 000e7f-6e6a60
8 100/1000T 20000 128 Forwarding | 000e7f-6e6a60
9 100/1000T 20000 128 Disabled |
10 100/1000T 20000 128 Disabled |
11 100/1000T 20000 128 Disabled |
12 100/1000T 20000 128 Disabled |
13 100/1000T 20000 128 Disabled |
14 100/1000T 20000 128 Disabled |
15 100/1000T 20000 128 Disabled |
16 100/1000T 20000 128 Disabled |
17 100/1000T 20000 128 Disabled |
18 100/1000T 20000 128 Disabled |
19 100/1000T 20000 128 Disabled |
20 100/1000T 20000 128 Disabled |
21 100/1000T 20000 128 Disabled |
22 100/1000T 20000 128 Forwarding | 000e7f-6e6a60
23 100/1000T 20000 96 Forwarding | 000e7f-6e6a60
24 1000SX 20000 112 Forwarding | 000480-789503

Switch 2:
HP2824 NoFW Backup# show span

Rapid Spanning Tree (RSTP) Information

STP Enabled : Yes
Force Version : RSTP-operation

Switch Priority : 40960 Hello Time : 2
Max Age : 20 Forward Delay : 15

Topology Change Count : 1512
Time Since Last Change : 33 hours

Root MAC Address : 000480-789503
Root Path Cost : 40000
Root Port : 23
Root Priority : 0

Root Guard Ports :
TCN Guard Ports :
BPDU Protected Ports : 2,5-18,21-22
BPDU Filtered Ports :

Port Type Cost Priority State | Designated Bridge
----- --------- --------- -------- ---------- + -----------------
1 100/1000T 20000 144 Blocking | 001db3-943700
2 100/1000T 200000 144 Forwarding | 000f20-ce9f00
3 100/1000T 20000 144 Blocking | 001db3-94acc0
4 100/1000T 200000 144 Blocking | 000e7f-6e6a60
5 100/1000T 20000 144 Disabled |
6 100/1000T 20000 144 Disabled |
7 100/1000T 20000 144 Disabled |
8 100/1000T 20000 144 Disabled |
9 100/1000T 20000 144 Disabled |
10 100/1000T 20000 144 Disabled |
11 100/1000T 20000 144 Disabled |
12 100/1000T 20000 144 Disabled |
13 100/1000T 20000 144 Disabled |
14 100/1000T 20000 144 Disabled |
15 100/1000T 20000 144 Disabled |
16 100/1000T 20000 144 Disabled |
17 100/1000T 20000 144 Disabled |
18 100/1000T 20000 144 Disabled |
19 100/1000T 20000 144 Blocking | 000e7f-6e6a60
20 100/1000T 20000 144 Blocking | 000f20-cf9200
21 100/1000T 20000 144 Disabled |
22 100/1000T 20000 144 Disabled |
23 100/1000T 20000 96 Forwarding | 000e7f-6e6a60
24 1000SX 20003 112 Blocking | 000480-e02003

> The two rack switches (2610s) they have
> spanning tree disabled?
No they have spanning tree enabled - cause when i disable it both ports on Switch 1 + 2 are in forward state. It seems, that the 2610 does not transmit bpdu packets when stp is disabled - newest firmware is installed.

Information regarding the switch:
2610-24
Version: R.11.04, ROM R.10.06

[Richard Brodie_1]

You have bpdu-protection on switch 2, port 2. I would start by disabling that.

[Stefan Priebe]

Oh sorry - the relevant ports in my example and in show span do not match. In the show span it is Port 3+4 on both.

[Richard Brodie_1]

If it supports it, what does show span detail say? Maybe as an attachement, it's fairly long.

[Stefan Priebe]

Thanks for your help.

Here are the absolutely correct port numbers:
Switch 1:
Port 4: Rack 2
Port 8: Rack 1

Switch 2:
Port 1: Rack 1
Port 3: Rack 2

and attached the .txt file.

[Richard Brodie_1]

If I'm reading ths right: it appears that Router 1 is the root bridge in your spanning tree.

Switch 1, port 24 has 0 RSTP BPDUs received. That implies Router 1 is running plain old STP.

[Stefan Priebe]

Mhm the router is a foundry bigiron.

# show span
VLAN 2 BPDU cam_index is 32768 and the IGC and DMA master Are(HEX) 0 1 2 3
STP instance owned by VLAN 2

Global RSTP (IEEE 802.1W/D3) Parameters:

VLAN Root Root Root Prio Max He- Ho- Fwd Last Chg Bridge
ID ID Cost Port rity Age llo ld dly Chang cnt Address
Hex sec sec sec sec sec
2 0000000480789503 0 Root 0000 20 2 1 15 198070 319 000480789503

Port STP Parameters:

Port Prio Path State Fwd Design Designated Designated
Num rity Cost Trans Cost Root Bridge
Hex
1/4 80 20000 FORWARDING 2 0 0000000480789503 0000000480789503
1/7 80 20000 FORWARDING 1 0 0000000480789503 0000000480789503
1/8 80 20000 FORWARDING 1 0 0000000480789503 0000000480789503

#show span detail

======================================================================
VLAN 2 - MULTIPLE SPANNING TREE (MSTP) ACTIVE
======================================================================
Bridge identifier - 0x0000000480789503
Active global timers - Hello: 0

Port 1/4 is FORWARDING
Port - Path cost: 20000, Priority: 128, Root: 0x0000000480789503
Designated - Bridge: 0x0000000480789503, Interface: 3, Path cost: 0
Active Timers - Hold: 0
BPDUs - Sent: 4098491, Received: 316
Port 1/7 is FORWARDING
Port - Path cost: 20000, Priority: 128, Root: 0x0000000480789503
Designated - Bridge: 0x0000000480789503, Interface: 6, Path cost: 0
Active Timers - Hold: 0
BPDUs - Sent: 4098253, Received: 0
Port 1/8 is FORWARDING
Port - Path cost: 20000, Priority: 128, Root: 0x0000000480789503
Designated - Bridge: 0x0000000480789503, Interface: 7, Path cost: 0
Active Timers - Hold: 0
BPDUs - Sent: 4098269, Received: 23

Config:
spanning-tree priority 0
spanning-tree ethe 1/4 path-cost 20000
spanning-tree ethe 1/7 path-cost 20000
spanning-tree ethe 1/8 path-cost 20000
spanning-tree rstp

Any Idea?

[Stefan Priebe]

Switch 1 is connected to Port 1/4.

[Richard Brodie_1 · Accepted solution]

Heading out of my depth here but as far as I can tell from the Foundry web site:

spanning tree rstp doesn't enable rstp but an early draft(3) of it.

spanning-tree 802-1w is the real deal.

You might like to confirm with someone that actually understands those beasts though.

[Stefan Priebe]

you're abolutely correct - who can imagine that rtsp command is not rtsp. I've now configured it to 802-1w and will try it again on monday.

Thank you so much.

[Stefan Priebe]

It's working fine now. Only when i pull the main link to one of the racks the backuplink goes into learning state and it takes 5s to be online again. But all other pulls and put ins :-) are working fine.

I think the 5s outage is normal isn't it?