doubt switch config

Unanswered Question
Sep 10th, 2007
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Hi all,

I have seen some switch config and find some commands but I unable to understand faithfully coz. I am new.

Plz. experts can any body explain about these below config commands.

#priority-queue out

#mls qos vlan-based

#spanning-tree portfast

Thanks in advance,


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Overall Rating: 4 (2 ratings)


priority-queue out: by default on some platforms the priority queue is not enabled, so if you want use for instance LLQ you have to use this command to enable the priority queue on the particular interface

mls qos vlan-based: enables per-VLAN QoS for a Layer 2 interface

spanning-tree portfast: put immediately the port to forwarding state by skipping the STP states (blocking, listening, learning, forwarding). Used on access port where _only_ host connected. Wise to use bpdu guard together.

Hope it helps, rate if does


ilnaiduccna Tue, 09/11/2007 - 01:02
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Hi Krisztian,

Thanks for your early reply.

One more reservation that can u give some explanation about QoS and LLQ.

These are all actually using in VLAN concept only or any other.


mahmoodmkl Tue, 09/11/2007 - 01:15
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Qos means as u know quality of service i.e providing better treatment for selected network traffic.

LLQ means low-latency queing which is the current queing method for dealy sensitive traffic.



ilnaiduccna Tue, 09/11/2007 - 01:51
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Thanks Mr. Mahmood and Krisztian for their good enlightenments.




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