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2.13.1. MAC Learning and Aging
Learning Process:
- Frame arrives on a switch port
- Switch reads the source MAC address
- Switch adds an entry: "MAC X is reachable via Port Y"
- Entry includes a timestamp for aging
Aging:
- Default aging time: 300 seconds (5 minutes)
- If no frames from a MAC address in that time, entry is removed
- Aging keeps the table current and manageable
Switch# show mac address-table
Mac Address Table
-------------------------------------------
Vlan Mac Address Type Ports
---- ----------- -------- -----
1 0011.2233.4455 DYNAMIC Gi0/1
1 0011.2233.4466 DYNAMIC Gi0/2
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Written byAlvin Varughese
Founder•20 professional certifications