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New Member

Limit Bandwidth on a 3750

Hello All,

I would like to limit the amount of outbount smtp traffic on a particular interface to 256 Kbps. Can you please help me

with the best method how I can accompolish this ? I have tried to use a policy map but it appears not to be working.



New Member

Limit Bandwidth on a 3750

Try this:

ip access-list extended SMTP_ACL

permit tcp any gt 1024 any eq 25

class-map match-any qos-set-SMTP

  match access-group name SMTP_ACL


class qos-set-SMTP

   set dscp cs1

class-map match-any qos-SMTP

match ip dscp cs1


class qos-SMTP

bandwidth percent <%>


  service-policy output OUTBOUND-TRAFFIC

  service-policy input INBOUND-TRAFFIC

New Member

Limit Bandwidth on a 3750

Thanks for the reply Eloy, but unfortunately I receive a message "Assigning a policy map to the output side of an interface not supported"

Any other ideas ?

Super Bronze

Re: Limit Bandwidth on a 3750


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It's a bit involved, but you could enable QoS, map your SNMP traffic to a single egress queue, and enable shaping for it.

Or, if you get SNMP mapped into a specific egress queue, you might also just give it a different bandwidth proportion.  This would allow SNMP additional bandwidth if the additional bandwidth was otherwise unused.