SplitVlan Cisco Cat6k

[Madhu Aayanam]

hi,

i had about a decade ago come across

 a feature called splitVlan in cat6k switch series

. I have done extensive online search for understanding what they are but I am finding no documentation in this regard. Could someone kindly clarify what

 splitVlans

are and how to configure them if need be. 

Regards

[balaji.bandi]

feature called splitVlan in cat6k switch series

not that i recall this, what is the goal of this ? so we can suggest different config and method to achieve same goal.

[Madhu Aayanam]

my query was to understand the theory of

splitvlan

not looking to implement/config currently. i am doing some documentation work on vlans and reached a point where i remembered about

SplitVlans

and wanted to understand more.

[Jon Marshall]

I suspect the reason you can't find any documentation on it is because there is no such feature but happy to be proved wrong. 

Jon

[Giuseppe Larosa · Accepted solution]

Hello @Madhu Aayanam ,

I agree with @Jon Marshall  I have never heard of  a feature named

SplitVlan

I have read and we have discusssed about procedures   on how to split a VLAN with too many hosts in multiple VLANs for efficency reasons   ( to reduce the noise caused by broadcast traffic, multicast traffic and unknown unicast).

There are environments specially in some factory where they abused of the

ip address secondary concept/command

placing all new subnets under the same SVI interface Vlan and creating a single broadcast domain with thousands of hosts and twenty different IP subnets.

Here, the suggestion is to collect information from ARP tables , CAM tables of switches and to create new L2 VLANs and new L3 interface VLANs to move a secondary subnet in each of them and moving access ports of hosts in that subnet in the new VLAN.

But this is not a single command as you can understand but a migration procedure.

Hope to help

Giuseppe

[Madhu Aayanam]

Thank you, makes sense and probably was what I might have come across. I am referring to some discussion around 15 years ago. I now understand this is no configurable feature.

[MHM Cisco World]

may be you talk about private VLAN where same VLAN is divide for security.
may be 

[Georg Pauwen]

Hello,

I do not remember, ever, seeing that feature. I am pretty confident in saying that there is (or was) no such feature a

SplitVlan