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New Member

C6509 problem


I run on C6500 (SUP720) IOS 12.2(33)SXI5 and sometimes I got sporadic problems on production systems that I find really difficult troubleshoot.

The only thing I found strange is the following amount of STP active ports:

#sh spanning-tree summary totals

Switch is in rapid-pvst mode

Root bridge for: xxx

EtherChannel misconfig guard            is enabled

Extended system ID                      is enabled

Portfast Default                        is disabled

Portfast Edge BPDU Guard Default        is enabled

Portfast Edge BPDU Filter Default       is disabled

Loopguard Default                       is disabled

Platform PVST Simulation                is enabled

PVST Simulation Default                 is enabled but inactive in rapid-pvst mode

Bridge Assurance                        is enabled

UplinkFast                              is disabled

BackboneFast                            is disabled

Pathcost method used                    is short

Name                   Blocking Listening Learning Forwarding STP Active

---------------------- -------- --------- -------- ---------- ----------

424 vlans                  228         0        0       4037       4265

I see these number of virtual ports:

#sh vlan virtual-port      

Slot 1


Total slot virtual ports 1954

Slot 2


Total slot virtual ports 1944

Slot 3


Total slot virtual ports 262

Slot 4


Total slot virtual ports 398

Slot 5


Total slot virtual ports 423

Slot 6


Total slot virtual ports 423

Slot 7


Total slot virtual ports 372

Slot 8


Total slot virtual ports 74

Slot 9


Total slot virtual ports 148

Total chassis virtual ports 5998

On slot 1 and 2 I run WS-X6708-10GE.

My questions:

1) Why there is a difference in the total of STP active ports (4265) and vlan virtual port (5998) ?

2) Do you see any overcoming limits in these number ? to me total seems ok, I’m wondering if per slot or per port we overcome the limits of the device?

3) could be this issue the root cause of the problem ?


New Member

C6509 problem

I've found this link:

with this note I'm not sure about:

"In Release 12.2(33)SXI1 and later releases, these limits do not apply to WS-X67xx and WS-X65xx switching modules. (CSCsu30263)"

I'm also wondering about mac-address-table sincronization issue...

Do anybody have an idea/experience ?


Hall of Fame Super Gold

C6509 problem

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