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Mac Address cleared to fast but aging time set to 86400

infrajfpr
Beginner
Beginner

Hello,

We have a Cisco Core switch 6500 and leafs 2960 (ios 15.0(2)SE6).

The network is segmented, one vlan for each floor of the building, the STP is in mode rapid-pvst.

YY - workstation VLAN

XX - servers VLAN

We are configuring wake on lan across vlans, and some tests were successful. But after the workstation stay off for a while we can't power it on again, using wol. Troubleshooting this issue, we found out that 2960 is clearing the mac address-table in seconds after workstation is turned off.

The mac address-table aging-time is set for 24h, on 6500 it is set only for vlan YY, on 2960 it is set global.

In 6500 the mac address-table still filled:

  vlan   mac address     type    learn     age              ports

YY  2c41.3894.4f95   dynamic  Yes      10800   Ten/n 

SW_6509#show mac address-table aging-time
Vlan    Aging Time
----    ----------
Global  300
 YY    86400

SW_2960#show mac address-table aging-time
Global Aging Time: 86400
Vlan    Aging Time
----    ----------

We can't identify any topology change at the vlan where workstation is running:

SW_2960#show spanning-tree vlan YY detail
 VLANYY is executing the rstp compatible Spanning Tree protocol
  Number of topology changes 59 last change occurred 2w5d ago
          from StackPort2

What more can be clearing the mac address-table on Cisco 2960?

Down here is the configuration made for WoL:

WoL server is 10.8.XX.40

DHCP server is 10.8.XX.20

At 6500:

access-list 104 permit udp host 10.8.XX.40 any eq 7

ip forward-protocol udp 7

mac address-table aging-time 86400 vlan YY

interface VlanXX
 description #### VLAN Servers ####
 ip address 10.8.XX.253 255.255.255.0
 ip helper-address 10.8.XX.255
 ip directed-broadcast 104
 no ip proxy-arp
 standby 1 ip 10.8.XX.1
 standby 1 priority 110
 standby 1 preempt
 standby 1 track 1 decrement 20
end

interface VlanYY
 description #### VLAN floor 2 ####
 ip address 10.8.YY.253 255.255.255.0
 ip helper-address 10.8.XX.20
 ip directed-broadcast 104
 no ip proxy-arp
 standby 30 ip 10.8.YY.1
 standby 30 priority 110
 standby 30 preempt
 standby 30 track 1 decrement 20
end

AT 2960

mac address-table aging-time 86400

2 REPLIES 2

m.kafka
Enthusiast
Enthusiast

Dynamically learned MAC-table entries will be cleared if the switchport goes down, regardless of aging-time.

Only solution I can think of is port security with sticky learning:

http://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst2960/software/release/15-0_2_se/configuration/guide/scg2960/swtrafc.html?bookSearch=true#57753

Rgds, MiKa

Thank you for your reply m.kafka, but apply port-security mac-address sticky didn't solve my problem.

interface GigabitEthernet2/0/21
 description Teste WakeOnLan
 switchport access vlan YY
 switchport mode access
 switchport nonegotiate
 switchport voice vlan 15
 switchport port-security
 switchport port-security violation restrict
 switchport port-security mac-address sticky
 spanning-tree portfast
 spanning-tree bpduguard enable

The mac-address table still be cleaned after switchport goes down.

We are investigating how to change energy state of workstation's nic when they are shutdown.

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