NEC IP8800/S2400, IP8800/S6600 manual Failures on Using Spanning Tree, Checking filtering/QoS

3.Troubleshooting Functional Failures in Operation

[When Type displayed is Dot1x]

See "3.12.1 Communication Failure on Using IEEE 802.1X."

[When Type displayed is Wa]

See "3.12.2 Communication Failure on Using Web Authentication."

[When Type displayed is Macauth]

See "3.12.3 Communication Failure on Using MAC Authentication."

•Flooding is executed if the MAC address is not displayed.

•IP8800/S6700, IP8800/S6600, and IP8800/S6300:

If the communication still has been blocked despite no display appears, check to see if learning is suspended by MAC address learning limitation. In addition, check to see if the threshold in the Storm Control function is not too low.

•IP8800/S3600 and IP8800/S2400:

If the communication still has been blocked despite no display appears, check to see if the Suppress Port-to-Port Forwarding has been enabled. In addition, check to see if the threshold in the Storm Control function is not too low.

(b)Checking MAC address learning limitation [IP8800/S6700] [IP8800/S6600] [IP8800/S6300]

Execute the show mac-address-tablecommand with "learning-counter" parameter specified to check the information of MAC address learning limitation for the port and the VLAN to be checked.

>show mac-address-table learning-counter port 1/1-6
Date 2005/09/21 20:00:57 UTC
Port counts:6		Maximum Threshold		Status
Port	Count
1/1	3	-	-	-
1/2	1000	1000	800	Learning
1/3	0	-	-	-	<---1
1/4	50	60	40	Stop learning
1/5	45	60	40	Learning
1/6	0	60	40	Learning
>show mac-address-table learning-counter vlan
Date 2005/09/21 20:00:57 UTC
VLAN counts:4		Maximum Threshold		Status
ID	Count
1	3	-	-	-	<---1
100	1000	1000	800	Stop learning
200	0	-	-	No learning	<---2
4095	90	100	100	Learning

1.MAC address learning is suspended according to the MAC address learning limitation value. Frames from the unlearned source address are discarded without learning the MAC address. However, flooding is executed for frames of VLAN for which MAC address learning is suppressed.

2.Suppression of MAC address learning is set. Flooding is executed for received frames.

(4) Checking filtering/QoS

Certain packets may have been discarded by filtering, or packets may have been discarded through bandwidth monitoring, discarding control, or shaper of the QoS control. Check to see if the conditions of filtering and QoS control in the configuration have been set up correctly and if bandwidth monitoring, discarding control, or shaper has been set up appropriately for system operation. For the procedure, see "3.23.1 Checking Filtering/QoS Setting Information."

3.5.2Failures on Using Spanning Tree

If the spanning tree function is in use and a layer 2 communication failure occurs or the spanning tree operation status does not comply with the network configuration, isolate the problem according to the analysis method listed below. For the multiple spanning trees, check for each CIST or MST instance. For example, read the CIST route bridge or the route

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