Troubleshooting guide

4. Troubleshooting Communication Failures Due to a Resource Shortage
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4.1 MAC address table resource shortage
4.1.1 Checking the MAC address table resource usage
The Switch outputs operation log messages when the MAC address table entries reach 80% and
100% of the capacity limit. The table below lists the operation log message to be output.
Table 4-1: Operation log message that indicates resource usage
Communication is not affected immediately after the MAC address table entries reach 80% of the
capacity limit. If, however, entries continue to increase, the capacity limit might be reached. This
might lead to a resource shortage and cause problems such as the suppression of MAC address
learning. You need to pre-check the set value and the capacity limit value to avoid a situation where
the capacity limit is exceeded.
You can check resource usage of the MAC address table by using the
show system command. (For
details, see the manual Operation Command Reference.)
4.1.2 Actions to be taken when a MAC address table resource shortage
occurs
When the MAC address table entries reach the capacity limit, the Switch outputs a log message
corresponding to the triggers listed in the table below.
Table 4-2: Log message output triggers and log text
No. Trigger Operation log message
1 When the MAC address table entries reach 80% of
the capacity limit
MAC address table entries was beyond 80
percent of capacity.
2 When the MAC address table entries reach 100% of
the capacity limit
MAC address table entries exceeded
capacity.
No. Trigger Log message
1 MAC address learning
ARP/NDP learning
MAC address table entries exceeded capacity.
2 Static ARP/NDP registration MAC address table entries exceeded capacity.
3 Static MAC address registration The static MAC address entry can't be registered
at MAC address table. ( VLAN
<ID>,mac <MAC> )
#
4 Setting up of MAC address learning
suppression
The "no mac-address-table learning" entry can't
be registered at MAC address table. ( VLAN
<ID>
)
#
5 IEEE 802.1X
(port-based authentication, VLAN-based
authentication [static])
The 802.1X Supplicant MAC address can't be
registered at hardware tables.
#
Note: This log message is displayed when the show dot1x
logging
command is executed.
6 Enabling of the Ring Protocol
Additional Ring Protocol registration
AXRP <ring id> : The MAC address entry can't be
registered at hardware tables.
7 IGMP snooping registration IGMP snooping: The number of the IGMP snooping
entry exceeded the capacity of this system.
8 MLD snooping registration MLD snooping: The number of the MLD snooping
entry exceeded the capacity of this system.