If ARP refresh is enabled, the switch resends ARP requests for the host at 3/4 of the configured ARP timer value. is it using virtual mac-address, virtual IP address etc. In a lot of these situations when the server fails over it can do a gratuitous arp ie. nobody asked it it just resends it's. Understanding and managing the ARP cache timeout is essential for optimizing network performance, enhancing security, and ensuring seamless communication between devices. Is this value a fixed one (we send an ARP request 1 minute before aging) or is it a relative value (x % of the timeout. The Address Resolution Protocol (ARP) is critical for resolving IP addresses to MAC addresses within Layer 2 and Layer 3 networks. In Cisco devices, ARP entries are stored in a cache with a predefined aging timer. The Cisco default ARP timer is typically set to 14400 seconds (4 hours). ARP table issues can lead to network connectivity problems, packet loss, slow performance, or even security vulnerabilities like ARP spoofing.
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