ESW 500 Spanning Tree Protocol

Hi:
I have designed my network as Follows:
Cisco Catalyst 3750G Stack as the Core Switches
Cisco ESW 500 Switches as the Edge switches
I am trying to configure Spanning tree on my network with The Core Switches as the root. But i am having a problem with that.
I set the Catalyst 3750 as the root Bridge for all Vlans. But i am having a hard time to configure that on the ESW 500 Switches, as there is no place to configure Per VLAN spanning tree.
Once I configure trunk Ports between the Core and the Edges. The Edge Switches don't consider the the Catalyst 3750G as the root, although it is configured with 0 Periority.
Can you please help me with that?

Hi Mohamed,
Thank you for participating in the Small Business support community. My name is Nico Muselle from Cisco Sofia SBSC.
The reason for this not to work is the following : The ESW switches do not support PVST(+) or PVRST like the 3750G does, on the other hand, they support STP, RSTP, and MSTP (MSTP is not supported on the 3750)
So, keeping this in mind, it will not be possible to implement your STP per vlan. In this scenario however, where you set the 3750 as a root bridge for all VLANs, you could easily use RSTP, which is functional on both 3750 and ESW500 switches.
Hope this helps.
Best regards,
Nico Muselle
Sr. Network Engineer - CCNA

Similar Messages

  • Integrated switch - supports STP/RSTP? (Spanning Tree Protocol)

    Greetings all..
    As this device includes a 3-port switch, which can be integrated with the rest of the network, does it support either Spanning Tree Protocol (802.1d) or Rapid Spanning Tree Protocol (802.1w)?
    Neither protocol is terribly difficult to implement, and since these things are so heavily marketed in the education space, it seems like it's a feature that should be there.
    That said, when I look at the switch port that the AEBS is connected to (in bridge mode, obviously), there is no interaction with STP or RSTP. Is there some sort of "friendly" name for the option in the AirPort Utility that's eluding me?
    While I'm not going to create loops in the network by cabling this up, I can't count on someone else coming behind me doing the wrong thing...

    I have had sniffers on LAN ports off various AirPort AP before, never a sign of a BPDU. I am fairly certain that it does not support Spanning Tree.

  • Redundant connection, spanning tree protocoll

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  • Which spanning tree protocol is preferred PVST or rapid-PVST and why?

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    Disclaimer
    The Author of this posting offers the information contained within this posting without consideration and with the reader's understanding that there's no implied or expressed suitability or fitness for any purpose. Information provided is for informational purposes only and should not be construed as rendering professional advice of any kind. Usage of this posting's information is solely at reader's own risk.
    Liability Disclaimer
    In no event shall Author be liable for any damages whatsoever (including, without limitation, damages for loss of use, data or profit) arising out of the use or inability to use the posting's information even if Author has been advised of the possibility of such damage.
    Posting
    As Alex has noted, normally rapid-PVST should be preferred.
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  • Spanning Tree Protocol

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  • Different spanning tree protocols behavior

    Hi,
    This is my first time posting a question, so apologies if I missed something.
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    It usually happens when people add additional switches over time and configure them using RSTP.
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  • How to implement uplink redundancy and spanning tree in SFP-300 switches

    We have several Small Business 300 Series Managed Switches, the 10/100 ones with PoE, the first generation ones.
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    I'm sure spanning tree is a checkbox somewhere in the web interface.
    How does one implement uplink redundancy besides interconnecting the switches plus turning on spanning tree (RSTP)??
    Thank you, Tom
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    Hello Thomas,
    Thanks for using the Cisco Small Business eSupport Community. I've looked through the articles that are available in our Knowledge Base and found a few that I hope will be able to assist you in setting up spanning tree and link redundancy on your SFP300s:
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    Link Aggregate Group (LAG) Configuration on 200/300 Series Managed Switches
    And for your question on setting up STP, here are a few articles with additional information:
    Configure Spanning Tree Protocol (STP) Status and Global Settings on 200/300 Series Managed Switches
    Setup Spanning Tree Protocol (STP) on a Interface on the 300 Series Managed Switches
    I hope that this information helps! Please remember to mark your question as answered and rate if this solves your problem.
    Best,
    Gunner

  • What is the command to check the changes in the spanning-tree topology?

    What is the command to check the changes in the spanning-tree topology?

    Hi,
    Few commands which would help are:
    1- Show spanning-tree detail
    2-show spanning-tree detail | in ieee|from|occur|is exec  >> This will give from were the changes occuring- Ex:
    C6K1#show spanning-tree detail | in ieee|from|occur|is exec  
     VLAN0001 is executing the rstp compatible Spanning Tree protocol
      Number of topology changes 9536 last change occurred 00:00:29 ago
              from GigabitEthernet4/6
    3- show spanning-tree active  *& show spanning-tree root >> Will give you the root information.
    4-  show spanning-tree inconsistentports >> If there are any port which are inconsistent state due to STP features.
    STP running MST:
    ===============
    show spanning-tree mst configuration  >> Need to check and match the same outputs with the other switches running in the same MST domain/region.
    show spanning-tree mst detail
    show spanning-tree mst <name of the region>
    Debug on STP:
    ============
    debug spanning-tree events/bpdu >> would be good but to be run with more cautious.
    HTH
    Inayath
    *Plz rate if this info is usefull.

  • Nexus spanning tree pseudo configuration

    Hi
    I am trying to understand the pseudo configuration commands in a Nexus hybrid topology.
    I have vlans a, b and c only in the vPC side of the topology.  I have peer switch configured and the same stp priority on both switches.
    In the standard Spaning-tree topology I have completely seperate vlans x, y and z.
    What should I be configuring in the pseudo config section ?  Do I define a pseudo root priority for all vlans a, b, c and x, y, z or just for the standard spanning tree vlans x, y and z.  I need to avoid and, even short, spanning tree outages if I take one Nexus out of service for a short time.
    My thinking is that if one Nexus is out of service the physical mac will be used and potentially reduce the root priority of the vPC vlans causing a TCN and STP recalculation in vlans a, b and c.  This can be avoided by configuring a pseudo root priority for all Vlans lower than the current spanning tree priority shared by the vPC peers.  Is this correct ?  However, since I have a shared priority of 8192 on current vPC vlans will configuring, for example, a pseudo root priority of 4096 on those vPC vlans won't this also cause the TCN and recalculation I am trying to avoid ?  Is the benefit of the pseudo root config only obtained if it is configured at the start when the vPC is formed and prior to the peer switch command being issued ?
    Thanks, Stuart.

    Hi Ajay,
    It is recommended that switch-to-switch links are configured with the spanning-tree port type normalcommand. The one exception is the vPC peer-link which is recommended to configure with the spanning-tree port type network command.
    Take a read of the Best Practices for Spanning Tree Protocol Interoperability from page 56 of the vPC Best Practice Design Guide for further information on this.
    Regards

  • SF 300 Serires switch not participating in spanning tree?

    I just purchased an SF300-24 managed switch and I am running it in layer3 mode. I am testing it out right now and have it connected to two 2950 switches. The SF300 is connected to each 2950 with a four port etherchannel running LACP. When looking at spanning tree all three switches are configured the same when it comes to hello, forward, max age and all three are in RSTP mode. I adjusted the priorities so that the SF300 would be the root but that is not happening.
    I only have one VLAN as of right now set up and connectivity between the three switches is fine. The only problem seems to be that the two 2950 switches are the only two switches involved in the determination of the root bridge. Additionally it was the same way before I configured the etherchannel and had the switches connected over single trunk lines.
    I would appreciate if someone can expain to me why this is?
    Thanks in advance.

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    Thanks for your help but know I still cannot get the three devices to talk MST either,it is getting frustrating. If i add a redundant link and directly connect the two 2950's they immediately talk and configure MST. But when I remove that link no info is passed and both 2950's think they are the root even though the SF 300 priority is 0 on all three MST instances. On the SF300 I have the following settings:
    Spanning tree: enabled
    STP Operation Mode: Multiple STP
    BPDU Handling: Flooding
    Path Cost: Long
    Region name: test
    Revision: 1
    Max Hops: 20
    Max-age: 20
    Hello Time: 2
    Forward Delay: 15
    MST instance 1 Vlan 100
    Bridge Priority 0
    Designated Root Bridge: Self
    Root port: 0
    Root path cost: 0
    MST instance 2 Vlan 2-5
    Bridge Priority 0
    Designated Root Bridge: Self
    Root port: 0
    Root path cost: 0
    MST instance 0 all vlans not in instance 1 and 2
    Bridge Priority 0
    Designated Root Bridge: Self
    Root port: 0
    Root path cost: 0
    For MST interface Settings (both LAGs/instances are thesame)
    Int Priority: 128
    Path Cost: 20000
    Port State: Boundary
    Mode: RSTP
    Type: Boundary
    Designated port ID: 128
    Designated Cost: 0
    Remain Hops: 20
    Forward Transitions: 1
    The 2950 switches: (The only difference on the other switch is that the priority is 8192, and the MACs of course)
    MST00 is executing the mstp compatible Spanning Treeprotocol
      Bridge Identifierhas priority 4096, sysid 0, address 000b.460e.e040
      Configured hello time 2, max age 20, forward delay 15
      Current root haspriority 0, address 6c50.4dcb.334b
      Root port is 65 (Port-channel1), cost of root path is 50000
      Topology change flag not set, detected flag not set
      Number of topology changes 7 last change occurred 00:18:54 ago
              from Port-channel1
      Times:  hold 1, topology change 35, notification 2
              hello 2, max age 20, forward delay 15
      Timers: hello 0, topology change 0, notification 0
    Port 65 (Port-channel1) of MST00 is root forwarding
       Port path cost 50000, Port priority 128, Port Identifier 128.65.
       Designated roothas priority 0, address 6c50.4dcb.334b
       Designatedbridge has priority 0, address 6c50.4dcb.334b
       Designated port id is 128.1000, designated path cost 0
       Timers: message age 4, forward delay 0, hold 0
       Number of transitions to forwarding state: 1
       Link type ispoint-to-point by default, Boundary RSTP
       BPDU: sent 571,received 568
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      Bridge Identifierhas priority 4096, sysid 1, address 000b.460e.e040
      Configured hello time 2, max age 20, forward delay 15
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      Topology change flag not set, detected flag not set
      Number of topology changes 9 last change occurred 00:18:55 ago
              from Port-channel1
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              hello 2, max age 20, forward delay 15
      Timers: hello 0, topology change 0, notification 0
    Port 65 (Port-channel1) of MST01 is boundary forwarding
       Port path cost 50000, Port priority 128, Port Identifier 128.65.
       Designated root has priority 4097, address 000b.460e.e040
       Designated bridge has priority 4097, address 000b.460e.e040
       Designated port id is 128.65, designated path cost 0
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       Port path cost 50000, Port priority 128, Port Identifier 128.65.
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       Designated bridge has priority 4098, address 000b.460e.e040
       Designated port id is 128.65, designated path cost 0
       Timers: message age 0, forward delay 0, hold 0
       Number of transitions to forwarding state: 1
       Link type ispoint-to-point by default, Boundary RSTP
       BPDU: sent 611,received 0
    I notice that on MST01 and 02 they are not receiving BPDU’s,but I am not sure why or if that is the problem. It appears that the SF 300 is not sending BPDU packets for MST01 and 02, but is sending them for MST00. I also attached a capture. I captured the VLAN info for VLAN 100 which is in MST1. on the SF300, it appears that the SF 300 is recieving STP traffic but not generating any.

  • About Spanning tree problem

    I am a newbie for cisco switch.
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    Location A
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    switch A is redundancy switch , it will be active when primary Wi-FI Link and switch C is failure.
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    I would like to use spanning tree protocol for this case.
    As show my diagram, Can it achive failover for both switch and AP bridge link if I use this network design
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    John

    Hi John,
    This is achievable. The best way to do this is, If you can control the client switches,
    make the Client switch at location A, the root primary for the STP domain.
    On the Client switch at location B, make the STP cost high on the port towards the Switch B.
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    If the Wifi Bridge fails (AP3-AP4), the blocked link will start forwarding (make sure you are using rapid spanning tree for fast transition)
    Now the most important thing in this design is to make sure that the Wifi bridges pass STP BPDU traffic, if they don't, this will not work.
    Even if one of the switches fails on the active path, the backup path would still kick in.. 
    Let me know how you go with this..
    please rate helpful posts.. :)

  • Spanning tree problem

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    CAT4006 as PLWARBITES008 connected to:
    Connection 1
    ============
    PLWARBITES008 (G1/1)connected to PLWARBITMP001 (G1/0/8)
    Note: Connection down
    Connection 2
    ============
    PLWARBITES008 (G1/2)connected to PLWARBITMP002 (G1/0/8)
    NOte: Connection is up
    The connection 1 is down, however,
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    PLWARBITES008#sh cdp nei GigabitEthernet1/1 det
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    Entry address(es):
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    Version :
    Cisco IOS Software, Catalyst 4000 L3 Switch Software (cat4000-I5S-M), Version 12.2(25)EWA1, RELEASE SOFTWARE (fc1)
    Technical Support: http://www.cisco.com/techsupport
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    Hi:
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    regards
    Sandipani C

  • Spanning tree loops

    Hi we are having regular spanning tree issues in our network.
    On our config we do not have bpduguard configured from what I can see? Could this be an issue?
    What can be done centrally on the core switches to remove this threat? Are their default configs that a wise network administrator would apply as standard?
    HELP!

    HI Mike [Pls Rate if HELPS]
    Refer link below for examples and identify redundant links, root and backup root bridge etc..
    http://www.cisco.com/en/US/tech/tk389/tk621/technologies_tech_note09186a0080136673.shtml#intro
    Refer link for usage guidelines in implementing loopguard, bpdu guard etc..
    http://www.cisco.com/en/US/docs/switches/lan/catalyst4000/7.4/configuration/guide/stp_enha.html#wp1019943
    A Cisco router will give you a warning when you configure PortFast:
    SW1(config)#int fast 0/5
    SW1(config-if)#spanning-tree portfast
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    SW1(config-if)#
    Not only will the switch warn you about the proper usage of PortFast, but you must put the port into access mode before PortFast will take effect.
    But there is a chance - just a chance - that someone is going to manage to connect a switch to a port running Portfast. That could lead to two major problems, the first being the formation of a switching loop. Remember, the reason we have listening and learning modes is to help prevent switching loops. The next problem is that there could be a new root bridge elected - and it could be a switch that isn't even in your network!
    BPDU Guard protects against this disastrous possibility. If any BPDU comes in on a port that's running BPDU Guard, the port will be shut down and placed into error disabled state, shown on the switch as err-disabled. A port placed in err-disabled state must be reopened manually.
    BPDU Guard is off on all ports by default, and is enabled as shown here:
    SW1(config)#int fast 0/5
    SW1(config-if)#spanning-tree bpduguard enable
    It's a good idea to enable BPDU Guard on any port you're running PortFast on. There's no cost in overhead, and it does prevent the possibility of a switch sending BPDUs into a port configured with PortFast - not to mention the possibility of a switch not under your control becoming a root switch to your network!
    Refer link below for Understanding Spanning Tree Protocol:
    http://www.cisco.com/univercd/cc/td/doc/product/rtrmgmt/sw_ntman/cwsimain/cwsi2/cwsiug2/vlan2/stpapp.htm
    Hope i am Informative and this HELPS.
    PLS RATE if HELPS
    Best Regards,
    Guru Prasad R

  • Spanning tree in VPC

    Hi All,
    I have a topology like two vpc peer connected to down catalyst switch 3750 with VPC 51. My left switch is primary in VPC and other is secondary.
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    Hi Garg,
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    HTH
    Regards,
    VS.Suresh.
    *Plz rate the usefull posts *

  • Why did we really need this "spanning-tree extend system-id" command?

    Folks,
    On the Spanning tree protocol I understood how does this spanning-tree extend system-id command work.
    But I have not understood why it is in place? or why do we really need it?
    Regards,
    Nikhil Kulkarni.

    Hi Nikhil,
    The STP and RSTP standard specifications mandate that each switch running STP/RSTP must have a unique Bridge ID (BID). Because Cisco runs STP or RSTP in each VLAN separately (called PVST and RPVST or PVRST), in each VLAN, the switch behaves like a standalone (albeit virtual) switch and thus, each STP/RSTP instance is required to have a unique BID to comply with the standard. Simply, having X VLANs means having X separate STP/RSTP instances and X unique BIDs.
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    However, the consumption of MAC addresses this way was simply too large and ineffective. At the same time, having 65536 different values for priority in the BID was largely useless. So IEEE came with the idea of Extended System ID in which they reused a part of the priority field for a unique instance identifier. In Cisco's implementation, this field is populated with the VLAN number the STP/RSTP instance runs in. This easily and effectively makes the BID unique - even with the same priority for all VLANs on a single switch, and a single switch MAC address, multiple STP/RSTP instances running on this same switch with the same priority have different BIDs thanks to different VLAN numbers embedded into the BID.
    Some switch platforms actually allowed you to deactivate the Extended System ID and revert to the older style of assigning unique MAC addresses to individual STP/RSTP instance BIDs. That is why the command spanning-tree extend system-id exists in the first place. However, removing this command is only possible on those switching platforms which are equipped with 1024 MAC addresses for their disposal. Most new switching platforms have only 64 MAC addresses for their internal use, and while the spanning-tree extend system-id command is present in their configuration, you can not remove it. It is simply there to inform you that the Extended System ID is being used but you can not really deactivate it.
    Read more here:
    http://www.cisco.com/en/US/docs/switches/lan/catalyst6500/ios/12.2SXF/native/configuration/guide/spantree.html#wp1096536
    Best regards,
    Peter

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