SVI creation on L3 switches

[ajay kondapalli]

Hi,

I have one query on SVI creation L3 switches.  Do we have limitations to create SVIs ?  if so How many SVIs can we create maximum?

I heard, we have limitation based on platform?  is it true?

Thanks,

Ajay

[smehrnia]

Hi,

SVI limit is related to the vlan count limit... i know that in 3550, 3560 it is limitted to 1005.

Hope it Helps,

Soroush.

[kamran_Roostaee]

As you know SVI represents a VLAN of switch ports as one interface to the routing or bridging function  and only one SVI can be associated with a VLAN. current L3 switch platforms support maximum 4096 VlAN, so in teory this means that we can not have more than 4096 SVI. but in reality there is no defined limit to the number of SVIs and routed ports that can be configured in a L3 switch and it can be less than 4096, because the maximum number of SVI interfaces depends on the maximum number of IDB (Interface Descriptor Block) that the switch platform can use, if you assume that other resources, such as memory, CPU, and so forth, are available. In order to see the maximum number of IDBs you can use "show idb"

http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_tech_note09186a0080094322.shtml

[smehrnia]

I believe the 1 - 4094 is just the extended vlan numbering available on enhanced images, not the actual valid vlan count.

one could find out supported vlan count with show vlan status command. on L3 switches its 1005, on low ends 250.

the 4096 IDB enteries include the support for both HWIDB and SWIDB, so its not solely for holding SVI info

HTH,

Soroush.