3548 secondary ip on VLAN interface?

[yakimus.voks]

Why cannot I issue a secondary ip on VLAN interface?

swzg3_11#sh run int vlan 5

!

interface VLAN5

ip address 10.7.1.53 255.255.255.0

no ip directed-broadcast

no ip route-cache

end

swzg3_11#conf t

swzg3_11(config)#int vlan 5

swzg3_11(config-subif)#ip add 10.7.0.2 255.255.255.192 ?

  secondary  Make this IP address a secondary address

swzg3_11(config-subif)#ip add 10.7.0.2 255.255.255.192 secondary

swzg3_11(config-subif)#end

swzg3_11#sh run int vlan 5

interface VLAN5

ip address 10.7.1.53 255.255.255.0

no ip directed-broadcast

no ip route-cache

end

[cadet alain]

Hi,

what does sh ip int vlan5 reports?

Regards.

Alain.

[yakimus.voks]

swzg3_11#sh ip int vlan 5

VLAN5 is up, line protocol is up

  Internet address is 10.7.1.53/24

  Broadcast address is 255.255.255.255

  Address determined by non-volatile memory

  MTU is 1500 bytes

  Helper address is not set

  Directed broadcast forwarding is disabled

  Outgoing access list is not set

  Inbound  access list is not set

  Proxy ARP is enabled

  Security level is default

  Split horizon is enabled

  ICMP redirects are always sent

  ICMP unreachables are always sent

  ICMP mask replies are never sent

  IP fast switching is disabled

  IP fast switching on the same interface is disabled

  IP Null turbo vector

  IP multicast fast switching is disabled

  IP multicast distributed fast switching is disabled

  Router Discovery is disabled

  IP output packet accounting is disabled

  IP access violation accounting is disabled

  TCP/IP header compression is disabled

  RTP/IP header compression is disabled

  Probe proxy name replies are disabled

  Policy routing is disabled

  Network address translation is disabled

  WCCP Redirect outbound is disabled

  WCCP Redirect exclude is disabled

  BGP Policy Mapping is disabled

[glen.grant]

   A 3548 is a layer 2 only ancient switch .  That SVI is used to manage the switch only  and  cannot do any routing so hence you would never have a secondary ip on the switch just to manage it  and why it is not taking that command .  Cisco had a habit of leaving commands in the IOS even though they did not work .

[yakimus.voks]

That's really weird

I got a 3COM 3900 - also an ancient layer2 only switch -  but it allows to create several interfaces in different vlans and/or several ip-s in one vlan. Cant believe that cisco does not allow same features on the same epoch of switches ))

[Leo Laohoo]

You can create multiple VLANs with a 3500XL but you can only have one active VLAN management IP address at any one time. 

[glen.grant]

  I think you are getting layer 2 and 3 mixed up .  The cisco box can have many vlans created (layer 2) but it is not a layer 3 routing switch so there is no reason to have more than a single address on the switch to manage it as all routing is done on a different layer 3 device  which where all routing configuration would take place whether its a single  subnet or a subnet with multiple secondary ip's.