Igure – GarrettCom MNS-6K 4.1.4 User Manual
Page 233
M A G N U M 6 K S W I T C H E S , M N S - 6 K U S E R G U I D E
If a static VLAN is configured on at least one port of a switch, and that port has
established a link with another device, then all other ports of that switch will send
advertisements for that VLAN.
In the figure below, tagged VLAN ports on switch “A” and switch “C” advertise VLANs 22 and
33 to ports on other GVRP-enabled switches that can dynamically join the VLANs. A port can
learn of a dynamic VLAN through devices that are not aware of GVRP (Switch “B”.)
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IGURE
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– VLAN Assignment in GVRP enabled switches. Non GVRP enabled switches can impact
VLAN settings on other GVRP enabled switches
Switch A
GVRP On
Tagged
VLAN 22
Switch B
No GVRP
Tagged
VLAN 22
Switch C
GVRP On
Tagged
VLAN 22
Tagged
VLAN 33
Switch D
GVRP On
Dynamic
VLAN 33
Dynamic
VLAN 22
Switch E
GVRP On
Dynamic
VLAN 33
Dynamic
VLAN 22
1
5
11
12
3
6
7
2
Switch C
Port 5 dynamically joined VLAN 22
Ports 11, 12 belong to Tagged VLAN 33
Switch E
Port 2 dynamically joined VLAN 33
Ports 7 dynamically joined VLAN 33
Switch D
Port 3 dynamically joined VLAN 33
Ports 6 dynamically joined VLAN 33
Switch A
GVRP On
Tagged
VLAN 22
Switch B
No GVRP
Tagged
VLAN 22
Switch C
GVRP On
Tagged
VLAN 22
Tagged
VLAN 33
Switch D
GVRP On
Dynamic
VLAN 33
Dynamic
VLAN 22
Switch E
GVRP On
Dynamic
VLAN 33
Dynamic
VLAN 22
1
5
11
12
3
6
7
2
Switch C
Port 5 dynamically joined VLAN 22
Ports 11, 12 belong to Tagged VLAN 33
Switch E
Port 2 dynamically joined VLAN 33
Ports 7 dynamically joined VLAN 33
Switch D
Port 3 dynamically joined VLAN 33
Ports 6 dynamically joined VLAN 33
An “unknown VLAN” is a VLAN that the switch learns of by GVRP. For example, suppose that
port 1 on switch “A” is connected to port 5 on switch “C”. Because switch “A” has VLAN 22
statically configured, while switch “C” does not have this VLAN statically configured, VLAN 22
is handled as an “Unknown VLAN” on port 5 in switch “C”. Conversely, if VLAN 22 was
statically configured on switch C, but port 5 was not a member, port 5 would become a member
when advertisements for VLAN 22 were received from switch “A”. GVRP provides a per-port
join-request option which can be configured.
VLANs must be disabled in GVRP-unaware devices to allow tagged packets to pass through. A
GVRP-aware port receiving advertisements has these options:
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