Mapping 802.1Q Vlans To Isl Vlans - Cisco WS-C2950SX-48-SI Configuration Manual

Chapter 10 Configuring VLANs
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Console> (enable)

Mapping 802.1Q VLANs to ISL VLANs

Your network might have non-Cisco devices that are connected to the Catalyst 6500 series switches
through 802.1Q trunks or traffic from a non-Cisco switch that has VLANs in the Catalyst 6500 series
reserved range, 1002–1024.
The valid range of user-configured Inter-Switch Link (ISL) VLANs is 1–1000 (and 1002–1005; see
Table
is 0–4095. In a network environment with non-Cisco devices that are connected to Cisco switches
through 802.1Q trunks, you can map 802.1Q VLAN numbers that are greater than 1000 to ISL VLAN
numbers. If you use any VLANs in the extended range (1025–4094) for dot1q mappings, you cannot use
any of the extended-range VLANs for any other purpose.
802.1Q VLANs in the range 1–1000 are automatically mapped to the corresponding ISL VLAN. 802.1Q
VLAN numbers that are greater than 1000 must be mapped to an ISL VLAN in order to be recognized
and forwarded by Cisco switches.
These restrictions apply when mapping 802.1Q VLANs to ISL VLANs:
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78-15486-01
Name Status
notconnect 500
Security Secure-Src-Addr
disabled
Status Channel
mode
notconnect auto
Align-Err FCS-Err
- 0
Single-Col Multi-Coll Late-Coll
0 0
10-1) and 1025–4094. The valid range of VLANs that are specified in the IEEE 802.1Q standard
You can configure up to seven 802.1Q-to-ISL VLAN mappings on the switch.
You must map 802.1Q VLANs to Ethernet-type ISL VLANs.
Do not enter the native VLAN of any 802.1Q trunk in the mapping table.
When you map an 802.1Q VLAN to an ISL VLAN, traffic on the 802.1Q VLAN corresponding to
the mapped ISL VLAN is blocked. For example, if you map 802.1Q VLAN 2000 to ISL VLAN 200,
traffic on 802.1Q VLAN 200 is blocked.
VLAN mappings are local to each switch. Make sure that you configure the same VLAN mappings
on all appropriate switches in the network.
Catalyst 4500 Series, Catalyst 2948G, Catalyst 2980G Switches Software Configuration Guide
Vlan Level
normal
Last-Src-Addr
Channel Neighbor
status device
not channel
Xmit-Err Rcv-Err
0 0
Excess-Col Carri-Sen Runts
0 0
Configuring VLANs on the Switch
Duplex Speed Type
auto auto 10/100BaseTX
Shutdown Trap IfIndex
No disabled 12
Neighbor
port
UnderSize
0
Giants
0 0
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