Jon Marshall Thu, 02/07/2008 - 02:59
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Choose an unused subnet eg.

You need a L3 interface for this whether on a router or a L3 switch

int fa0/0

ip address


int vlan 2

ip address

on all your other switches allocate them an unused address from the above subnet and then

1) Create vlan 2

2) Create L3 interface for vlan 2

3) allocate address

4) set default-gateway

switch(config)# vlan 2

switch(config-vlan)# name management

switch(config)# int vlan 2

switch(config-if)# ip address

switch(config)# default-gateway

I have used vlan 2 in this example but you can use vlan 1 on your switches if you want, Cisco just recommend changing the management vlan from vlan 1.

I have assumed your switches are L2 switches only, so they will only be able to have one active L3 interface ie. vlan 1 or vlan 2, your choice.


ntmanjunath Thu, 02/07/2008 - 20:39
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We have one L3 switch and other 49 are L2 switch.

When I try the below said command,its shows error

Bad mask /25 for address

switch(config)# int vlan 2

switch(config-if)# ip address

fortis123 Fri, 02/08/2008 - 08:54
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Did you enable the below commands on L3 device..

ip subnet-zero, ip classless.

Try both, it might fix it.




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