sh vlan internal usage...

whoops... here's a wild one...


dsw2#sh vlan int usage

VLAN Usage
---- --------------------
1025 FastEthernet0/5
1027 Port-channel1

more on these two in a minute


the range of standard vlans on a switch is 1-1001 (1002-1005 are reserved for dinosaurs)
the extended vlan range is 1006-4094
would any enterprise need more than 1000? maybe...

by default the extended range is allocated by vlan allocation policy in ascending order...
from 1006 up to 4094... i just created vlan 4094 (vtp mode has to be globally transparent to use the extended range)

dsw2#sh vlan

VLAN Name                             Status    Ports
---- -------------------------------- --------- -------------------------------
4094 VLAN4094                         active

VLAN Type  SAID       MTU   Parent RingNo BridgeNo Stp  BrdgMode Trans1 Trans2
---- ----- ---------- ----- ------ ------ -------- ---- -------- ------ ------
1    enet  100001     1500  -      -      -        -    -        0      0
10   enet  100010     1500  -      -      -        -    -        0      0
20   enet  100020     1500  -      -      -        -    -        0      0
99   enet  100099     1500  -      -      -        -    -        0      0
100  enet  100100     1500  -      -      -        -    -        0      0
1002 fddi  101002     1500  -      -      -        -    -        0      0
1003 trcrf 101003     4472  1005   3276   -        -    srb      0      0
1004 fdnet 101004     1500  -      -      -        ieee -        0      0
1005 trbrf 101005     4472  -      -      15       ibm  -        0      0
4094 enet  104094     1500  -

as for the internal usage vlans above, i have/can find no other explanation besides:

f0/5 is i know an ipv6 capable port, and therefore special
and port-channel1 is special, because, it's special...

all i can figure is that the vlan allocation policy of  a given switch mandates that special usage ports are given a special extended vlan identifier...

because they are special