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

Mike mike-cisconsplist at tiedyenetworks.com
Sun Feb 9 19:34:06 EST 2014


Hello,

     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.

Mike-



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