Dell PowerConnect 5212 System User's Manual page 66

Command
map ip precedence
map ip precedence ip-precedence-value cos cos-value
show map ip precedence [interface]
map ip dscp
map ip dscp dscp-value cos cos-value
show map ip dscp [interface]
Example
Console(config)#map ip precedence
Console(config)#interface ethernet 1/5
Console(config-if)#map ip precedence 1 cos 1
Console(config-if)#exit
Console(config)#map ip dscp
Console(config)#interface ethernet 1/5
Console(config-if)#map ip dscp 1 cos 0
Console(config-if)#exit
Console(config)#exit
Console#show map ip dscp ethernet 1/1
DSCP mapping status: disabled
Port DSCP COS
--------- ---- ---
Eth 1/ 1 0 0
Eth 1/ 1 1 0
Eth 1/ 1 2 0
Eth 1/ 1 3 0
Usage
Enables IP precedence mapping (IP ToS) for the switch
Sets IP precedence priority (IP ToS priority) for a port or trunk interface (applies to all ports)
Shows the IP precedence priority map
Enables IP DSCP mapping for the switch
Sets IP DSCP priority for a port or trunk interface (applies to all ports)
Shows the IP DSCP priority map