
Switches maintain [MAC address table](/mac-address-table)s which are constructs, typically stored in [CAM type memory](/memory-cam-and-tcam),  that correspond [MAC address](/mac-address)es with physical interfaces on which those addresses have been detected.  Each [VLAN](/vlan) that has been configured within a switch maintains its own MAC address table.

However, when you want to display the MAC Address Table, the device consolidates all of the MAC address tables into a single set of output, indicating on which VLAN each MAC address has been observed.  For example, the following is a partial output of a production switch that has MAC addresses corresponding to multiple VLANs.

```
core_3850#show mac address-table
          Mac Address Table
-------------------------------------------

Vlan    Mac Address       Type        Ports
----    -----------       --------    -----
 All    0100.0ccc.cccc    STATIC      CPU
 All    0100.0ccc.cccd    STATIC      CPU
 All    0100.0ccc.ccce    STATIC      CPU
 All    0180.c200.0000    STATIC      CPU
 All    ffff.ffff.ffff    STATIC      CPU
   1    00c8.8b64.be99    DYNAMIC     Gi1/0/4
   1    00c8.8baa.6499    DYNAMIC     Gi1/0/3
 100    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 100    00c8.8b64.bed1    DYNAMIC     Gi1/0/4
 110    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 110    042a.e23e.64cd    STATIC      Vl110
 120    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 120    042a.e23e.64c8    STATIC      Vl120
 121    0015.5d07.b000    DYNAMIC     Gi1/0/2
 121    0015.5d07.b001    DYNAMIC     Gi1/0/2
 122    0024.1dc6.28cb    DYNAMIC     Gi1/0/3
 122    00c0.ee13.57f2    DYNAMIC     Gi1/0/4
 155    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 155    042a.e23e.64cd    STATIC      Vl155
 200    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 200    042a.e23e.64e2    STATIC      Vl200
 220    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 220    042a.e23e.64dd    STATIC      Vl220
 221    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 221    00ca.e540.bb20    DYNAMIC     Gi1/0/5
 600    0000.0c07.aca0    DYNAMIC     Gi1/0/1
 600    042a.e23e.64d6    STATIC      Vl600
 601    0000.0c07.aca1    DYNAMIC     Gi1/0/1
 601    042a.e23e.64fd    STATIC      Vl601
 707    001c.c073.22b5    DYNAMIC     Gi1/0/3
 707    00a0.0307.892d    DYNAMIC     Gi1/0/4
 123    042a.e23e.64da    STATIC      Vl123
 552    042a.e23e.64d5    STATIC      Vl552
 804    0000.0c07.ac68    DYNAMIC     Gi1/0/1
 804    0000.4845.04ee    DYNAMIC     Gi1/0/1
 904    0000.0c07.accc    DYNAMIC     Gi1/0/1
 904    3cce.73ac.37c5    DYNAMIC     Gi1/0/4
 119    00ca.e526.1b19    DYNAMIC     Gi1/0/2
 140    0017.c84a.d796    DYNAMIC     Gi1/0/2
 140    0017.c84c.b9f9    DYNAMIC     Gi1/0/2
 150    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 310    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 320    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 320    36de.f8bc.e6aa    DYNAMIC     Gi1/0/5
 507    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 507    1242.d23f.b117    DYNAMIC     Gi1/0/5
 720    00c8.8b64.be99    DYNAMIC     Gi1/0/4
 797    00ca.e526.1b19    DYNAMIC     Gi1/0/2
 797    e063.dac6.fd98    DYNAMIC     Gi1/0/2
 124    00ca.e526.1b19    DYNAMIC     Gi1/0/2
 124    0c73.2927.45e0    DYNAMIC     Gi1/0/2
 400    00c8.8b64.be99    DYNAMIC     Gi1/0/4
Total Mac Addresses for this criterion: 788
core_3850#
```

It is possible to limit the output to particular VLANs by issuing additional keywords like so:

`Switch# show mac address-table vlan 1`

## Links

https://networklessons.com/switching/how-does-a-switch-learn-mac-addresses

MAC address table - Switches maintain one table per VLAN

IS-IS - up-down bit

IS-IS multitopology support

IS-IS

ISDN

ISIS circuit-type command

ISP Peering

ISPs, tiers, transiting, and the Internet

Importance of self-study for CCIE or CCDE

Interface - configuring a range of interfaces

Interface - no carrier counter

Interface - show interfaces counters explained

Interface - unknown protocol drops

Interface MTU and Frame Handling

Interface speed and bandwidth

Interior Gateway Protocol (IGP)

Internet Exchange Point (IXP)

Internet Service Provider (ISP)

Intrusion prevention system (IPS)

Kron task scheduler

L2TPv3 over IPSec

L2TPv3

LACP

LAG - Multi-Chassis LAG

LFA - Topology Independent LFA

LFA, remote LFA, and how they work together in OSPF

LISP - map request and reply process

LISP - what is it

LISP and overlapping address spaces

LISP debug traffic between two EIDs

LISP host mobility use cases

LISP where EID-to-RLOC mappings originate

LISP

Layer 2 (L2) LISP

Layer 2 network

Link State Routing Protocols

Linux - Line continuation character backslash

Local Proxy ARP

Loop-Free Alternate (LFA) Fast Reroute (FRR)

Loop-Free Alternate (LFA) and remote LFA

Loop-free Network Design and FHRP Protocols

Loop-free layer 2 network design

Loops in layers 2 and 3

MAC - changing the MAC address on a switchport

MAC Access List EtherType

MAC Access List

MAC Address Table - Static assignment use cases

MAC address flapping

MAC address of all zeros

MAC address table - multiple entries of the same MAC address

MAC address table - multiple static entries

MAC address table - show command on Nexus device

MAC address table - static entry

MAC address table populated using source address field

MAC address table static multicast entry

MAC address table

MAC address

MPLS - BGP customer prefixes do not appear in the LFIB

MPLS - Connecting IPv6 sites over an IPv4 backbone

MPLS - Disabling IPv4 address family in BGP for VPNv4

MPLS - Ethernet over MPLS (EoMPLS)

MPLS - L3VPN BGP EIGRP redistribution

MPLS - L3VPN BGP OSPF Redistribution

MPLS - LDP source interface

MPLS - Layer 2 VPNs

MPLS - Multi-VRF CE

MPLS - OSPF redistributed routes appear as O IA

MPLS - Segment Routing over MPLS

MPLS - Transport Profile

MPLS - Using RSVP for Traffic Engineering

MPLS - Using the BGP Allow-AS in feature

MPLS - VPN label

MPLS - VPN redistributing default route from CE into BGP

MPLS - VPNv4 Labels are assigned per route

MPLS - Virtual Private Network (VPN)

MPLS - label distribution using MP-BGP

MPLS - label

MPLS - multiarea OSPF in the core

MPLS - network redundancy

MPLS - what is fate sharing

MPLS - what is seamless MPLS

MPLS 6PE uses two labels in the data plane

MPLS Bytes Label Switched in the LFIB

MPLS Customer Edge Router

MPLS L3 VPNs and the interaction between AS-Override and SoO

MPLS L3VPN Inter-AS Options

MPLS LDP Label Filtering

MPLS LDP Session Protection

MPLS LDP Targeted Hellos

MPLS LSR ID

MPLS Label Distribution Protocol

MPLS Label Distribution and Swapping

MPLS Label Edge Router

MPLS Label Switch Router

MPLS Layer 3 VPN communication between CE and PE routers

MPLS Layer 3 VPN communication between CE routers

MPLS Local Label Allocation Filtering

MPLS Penultimate hop popping

MPLS Route Distinguisher