[c-nsp] wisdom of switchport block ...

Randy randy_94108 at yahoo.com
Sun Feb 9 21:46:27 EST 2014

 You pose an interesting question wrt what the default should be.
I don't have that answer. On the same token, unknown unicast flooding is required for certain topologies to work - campus networks come to mind.
...Your network, you decide based on your topology what to leave-enabled and what to disable.


> From: Mike <mike-cisconsplist at tiedyenetworks.com>
>To: "cisco-nsp at puck.nether.net" <cisco-nsp at puck.nether.net> 
>Sent: Sunday, February 9, 2014 4:34 PM
>Subject: [c-nsp] wisdom of switchport block ...
>    I am looking at tightening up my subscriber access network and, if I understand the documentation correctly, 'switchport block unicast' will prevent a cisco switch (3560g in this case) from flooding unicast frames out any port so configured, unless the destination mac address was learned from that port. Is there any reason on earth why I would NOT want to have this as a standard default option? Arp would still work, as would dhcp and pppoe... trying to fathom how this could be bad? Would appreciate any insights!
>Thank you.
>cisco-nsp mailing list  cisco-nsp at puck.nether.net
>archive at http://puck.nether.net/pipermail/cisco-nsp/

More information about the cisco-nsp mailing list