Ping - Type of Service

ianwarb · ‎10-21-2004

I have been trying to investigate the ToS field in the extended ping command but cannot find much documentation on how to use it. Can this be used for effectively troubleshooting QOS configs and does anyone know where i can find more information on it.

thanks

Ian

thisisshanky · ‎10-21-2004

The TOS value by default is zero for all ping packets going out. So if you set this value, the TOS field in the ping packet will be set and send out. You should be able to test qos configs and see some counters getting hit by setting these TOS bits.

http://www.cisco.com/en/US/tech/tk365/tk554/technologies_tech_note09186a0080093f22.shtml

Sankar Nair
UC Solutions Architect
Pacific Northwest | CDW
CCIE Collaboration #17135 Emeritus

jitcherng · ‎10-21-2004

the ToS field is 1 byte long 0-255. your tos value will depends on the Qos techniques (ip precendence or DSCP)

ip prec occupies the first 3 bits of the ToS field. So for 'critical' ip prec packets, the ToS value will be 10100000 = 160

http://www.cisco.com/warp/public/cc/pd/iosw/ioft/iofwft/prodlit/difse_wp.htm