precautions while adding new swtich into network

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Sep 10th, 2008
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I am trying to 3750 sw into my core network what precautions need to take to avoid STP loops/root bridge election

For my all VLANS 4500 acting as a root bridge..



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Prashanth Krishnappa Wed, 09/10/2008 - 08:25
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Few things I would do

1)If using default STP root bridge priority in the network, set it manually on the 4500 to be root for all VLANs

2)If you are using VTP, check and make sure the config-revision on this 3750 is not higher than in the production switches. To be safe, configure VTP to be transparent on 3750 and then connect it to network.

Jon Marshall Wed, 09/10/2008 - 08:25
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Firstly i would strongly recommend that you add in the switch out of key production hours because when you add it there will have to be an STP convergence for any vlans that run across the trunk link to this 3750 switch.

That said key things to check

1) That all vlans have explicitly set the STP root and secondary already so that the 3750 cannot become the STP root.

2) VTP status. If you run VTP on your switches make sure that the 3750 has a VTP revision number of 0 before you connect it up.


sateeshk10 Wed, 09/10/2008 - 08:54
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I hope on uplink if i configure stp route guard,bpdu gaurd. will it ok..

how to configure root bridge for all the VLANS in core sw 4500




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