Re: C3750 maximum number of STP active process

James Lasky · ‎05-04-2011

Hi

I've a C3750 config in stack, I guess I reach the maximum number of STP active process since going up to 1999 the switch become crazy and not working.

Where can I find the limit on the cisco web site ?

Does anybody have the same problem ?

Tks

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

#sh spanning-tree summary totals
Switch is in pvst mode
Root bridge for: VLAN0002-VLAN0003, VLAN0005-VLAN0009, VLAN0011, VLAN0013
VLAN0016, VLAN0019, VLAN0030, VLAN0038-VLAN0041, VLAN0045, VLAN0059
VLAN0062-VLAN0063, VLAN0065-VLAN0068, VLAN0070, VLAN0072-VLAN0073, VLAN0075
VLAN0077-VLAN0078, VLAN0082-VLAN0083, VLAN0085, VLAN0088-VLAN0098, VLAN0107
VLAN0109-VLAN0110, VLAN0117, VLAN0119, VLAN0122, VLAN0130-VLAN0131
VLAN0139-VLAN0156, VLAN0158-VLAN0160, VLAN0165-VLAN0167, VLAN0170-VLAN0177
VLAN0179, VLAN0188-VLAN0189, VLAN0191-VLAN0192, VLAN0197, VLAN0199, VLAN020
VLAN0219, VLAN0245, VLAN0268, VLAN0286, VLAN0304, VLAN0306-VLAN0308
VLAN0323, VLAN0329-VLAN0330, VLAN0335, VLAN0350, VLAN0401-VLAN0402, VLAN040
VLAN0420-VLAN0421, VLAN0502, VLAN0504
Extended system ID           is enabled
Portfast Default             is disabled
PortFast BPDU Guard Default is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default            is disabled
EtherChannel misconfig guard is enabled
UplinkFast                   is disabled
BackboneFast                 is disabled
Configured Pathcost method used is short

Name Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
127 vlans 70 0 0 1913 1999

#sh ver
Cisco IOS Software, C3750 Software (C3750-ADVIPSERVICESK9-M), Version 12.2(46)SE, RELEASE SOFTWARE (fc2)
Copyright (c) 1986-2008 by Cisco Systems, Inc.
Compiled Thu 21-Aug-08 15:43 by nachen
Image text-base: 0x00003000, data-base: 0x01940000

ROM: Bootstrap program is C3750 boot loader
BOOTLDR: C3750 Boot Loader (C3750-HBOOT-M) Version 12.1(14r)EA1a, RELEASE SOFTWARE (fc1)

SAS05-3750 uptime is 17 weeks, 6 days, 40 minutes
System returned to ROM by power-on
System restarted at 16:04:29 MET Thu Dec 30 2010
System image file is "flash:/c3750-advipservicesk9-mz.122-46.SE.bin"

This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.

A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html

If you require further assistance please contact us by sending email to
export@cisco.com.

cisco WS-C3750G-24TS (PowerPC405) processor (revision G0) with 118784K/12280K bytes of memory.
Processor board ID CAT0848Y1UJ
Last reset from power-on
12 Virtual Ethernet interfaces
56 Gigabit Ethernet interfaces
The password-recovery mechanism is enabled.

512K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address       : 00:12:D9:32:29:80
Motherboard assembly number     : 73-7058-11
Power supply part number        : 341-0045-01
Motherboard serial number       : CAT08480AFJ
Power supply serial number      : LIT0838090X
Model revision number           : G0
Motherboard revision number     : A0
Model number                    : WS-C3750G-24TS-E
System serial number            : xx

Hardware Board Revision Number : 0x09

Switch Ports Model              SW Version            SW Image
------ ----- -----              ----------            ----------
*    1 28    WS-C3750G-24TS     12.2(46)SE            C3750-ADVIPSERVICESK9-M
     2 28    WS-C3750G-24TS     12.2(46)SE            C3750-ADVIPSERVICESK9-M

Switch 02
---------
Switch Uptime                   : 17 weeks, 6 days, 26 minutes
Base ethernet MAC Address       : 00:12:7F:82:4B:80
Motherboard assembly number     : 73-7058-11
Power supply part number        : 341-0045-01
Motherboard serial number       : CAT08440L92
Power supply serial number      : PHI082602G8
Model revision number           : G0
Motherboard revision number     : A0
Model number                    : WS-C3750G-24TS-E
System serial number            : xx

Configuration register is 0xF

#

IAN WHITMORE · ‎05-04-2011

Up to 1005 VLANs per switch or stack and up to 128 spanning-tree instances per switch are supported.

Ref:

http://www.cisco.com/en/US/prod/collateral/switches/ps5718/ps5023/product_data_sheet0900aecd80371991.html

HTH,

Ian

James Lasky · ‎05-04-2011

Hi Ian

I guess this is not the point.

With 100 vlans, with 100 stp istances (pvst+) and 30 trunks configured with all vlans passing, we get 3000 stp (virtual ports) processes and the switch would not work...

Tks

IAN WHITMORE · ‎05-04-2011

So the question is, do you need all VLANS on all trunk ports? With VTP pruning or hard coding the trunks to allow only the vlans they need....on another note, could it be a memory issue? Maybe the switch just goes mad because it has to send so many copies of the BPDUs on the ports.

James Lasky · ‎05-04-2011

Correct,

But i need to know before which is the scaling limit of 3750.

I found the limit for 6500 (1800 processes per line card and 15000 per chassis if i remember well) but not for 3750...

I found this:

http://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a00800951ac.shtml

Just a sentence like

"make sure that this number does not exceed the maximum number supported for each Supervisor Engine type."...