3Com WX2200 3CRWX220095A manual Using ACLs to, Change CoS, Filtering Based on, Dscp Values

Using ACLs to Change CoS 399

Using ACLs to	For WMM or non-WMM traffic, you can change a packet’s priority by
Change CoS	using an ACL to change the packet’s CoS value. A CoS value assigned by
	an ACE overrides the CoS value assigned by the switch’s QoS map.
	To change CoS values using an ACL, you must map the ACL to the
	outbound traffic direction on a MAP port, Distributed MAP, or user VLAN.
	For example, to remap IP packets from IP address 10.10.20.5 that have IP
	precedence value 3, to have CoS value 7 when they are forwarded to any
	10.10.30.x address on Distributed MAP 2, enter the following
	commands:
	WX1200# set security acl ip acl1 permit cos 7 ip 10.10.20.5
	0.0.0.0 10.10.30.0 0.0.0.255 precedence 3
	success: change accepted.
	QX1200# set security acl ip acl1 permit any
	success: change accepted.
	WX1200# commit security acl acl1
	success: change accepted.
	WX1200# set security acl map acl1 ap 2 out
	success: change accepted.
	The default action on an interface and traffic direction that has at least
	one access control entry (ACE) configured, is to deny all traffic that does
	not match an ACE on that interface and traffic direction. The permit any
	ACE ensures that traffic that does not match the first ACE is permitted.
	Without this additional ACE at the end, traffic that does not match the
	other ACE is dropped.
Filtering Based on	You can configure an ACE to filter based on a packet’s Differentiated
DSCP Values	Services Code Point (DSCP) value, and change the packet’s CoS based on
	the DSCP value. A CoS setting marked by an ACE overrides the CoS
	setting applied from the switch’s QoS map.