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Cisco HSRP CAM vs ARP timeout

Last updated on December 25, 2018

        Today we received email from our ISP saying they are performing maintenance on their network so if you have HSRP connectivity with them in that case you need to clear <code>ARP table</code> or  reduce <code>ARP timeout</code> 
We do have HSRP connectivity with our ISP and following i found where i got confused.
#show mac address-table aging-time
Vlan    Aging Time  Configured Aging Time
----    ----------  ---------------------
Global Vlan Admin Age: 300
   1    300         300
   2    300         300
On interface: ARP timeout 4 hour
#sh int te1/50
TenGigabitEthernet1/50 is up, line protocol is up (connected)
  Hardware is Ten Gigabit Ethernet Port, address is 68ef.bd75.7370 (bia 68ef.bd75.7370)
  Description: ISP_A
  MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec,
     reliability 255/255, txload 33/255, rxload 36/255
  Encapsulation ARPA, loopback not set
  Keepalive set (10 sec)
  Full-duplex, 10Gb/s, link type is auto, media type is 10GBase-LR
  input flow-control is on, output flow-control is off
  ARP type: ARPA, ARP Timeout 04:00:00
  • what are those two timeout?
  • in Document saying you should keep CAM timeout and ARP timeout equal but how?
  • When ISP say you should reduce ARP timeout does that means only for specific interface which is connected to their router or whole switch?

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