Higher Education

Reply
This is an open group. Sign in and click the "Join Group" button to become a group member and start posting.
Frequent Contributor I

Re: Broadcast Multicast ( BCMC ) Bonjour Problem


@cjoseph wrote:

@Ryan wrote:
I'm glad you are acknowledging how large broadcast domains are bad regardless of vendor. I agree. There seems to be a philosophy manifesting inside Aruba that one (or more) large subnets be used for clients and to just let the controller filter things out.

To be clear, large subnets work just fine on wireless if you have broadcast controls in place.  You cannot however expect to not have broadcast filtering in place and have the same performance.  If bonjour applications are required, you run Airgroup.


I think large wireless only subnets are OK, the main issue seems to be related to subnets that span wired and wireless devices - then you start having some issues when you dont do something with your broadcasts.  I have seen wifi networks where 60% of the traffic was broadcasts because of this configuration...  And the admins still had no idea why this was happening....

 

It is a frustrating issue, that is easily corrected, and in my opinion manageable subnets just make things easier for everything. 

Highlighted
Guru Elite

Re: Broadcast Multicast ( BCMC ) Bonjour Problem



I think large wireless only subnets are OK, the main issue seems to be related to subnets that span wired and wireless devices - then you start having some issues when you dont do something with your broadcasts.  I have seen wifi networks where 60% of the traffic was broadcasts because of this configuration...  And the admins still had no idea why this was happening....

 

It is a frustrating issue, that is easily corrected, and in my opinion manageable subnets just make things easier for everything. 


Danstl,

 

You can have wired and wireless in the same VLAN as long as you ensure that you drop/control broadcasts on ALL WLANs, and it will certainly work.  You do NOT want to have them in the same VLAN because it seriously complicates troubleshooting.  Running a large subnet WLAN without broadcast controls more often that not makes it unusable.  It just gets worse when you add wired traffic.

 

Recap:

- Your users can keep their large subnets, even with wired clients as long as you enable broadcast controls.

- The downside is that it complicates troubleshooting when wired and wireless are in the same VLAN

- If those users run bonjour applications, they can run Airgroup code, where you can do that with broadcast controls, and it will work.

 


*Answers and views expressed by me on this forum are my own and not necessarily the position of Aruba Networks or Hewlett Packard Enterprise.*
ArubaOS 8.4 User Guide
InstantOS 8.3 User Guide
Airheads Knowledgebase
Airheads Learning Videos
Aruba Central Documentation
Sign up for Security Alerts
Aruba Technical Webinars
Super Contributor I

Re: Broadcast Multicast ( BCMC ) Bonjour Problem

Once a client's packet is decapsulated at the controller and (assuming the destination is not local to one of the controller's tunnels) is forwarded out the controller's uplink to the distribution layer, does the controller filter these broadcasts? Or, does it only filter broadcasts towards the controller (not away)? My understanding was that the filtering occurs in the direction towards the client, not away from the client.
==========
Ryan Holland, ACDX #1 ACMX #1
The Ohio State University
Search Airheads
cancel
Showing results for 
Search instead for 
Did you mean: