cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
2212
Views
0
Helpful
6
Replies

Testing QOS EF packets with ping from L3 switch

hmc2500
Level 1
Level 1

I have an uplink configured (on a 3850 Catalyst L3 switch) with the following policy map and priority que

policy-map priority-queue
class voice
priority level 1

int gi1/0/48

service-policy output priority-queue

 

However when I ping I don't see any EF packets being send on the interface. Am I missing something?

ping switch2 source 10.16.10.1 tos 184 repeat 200
Type escape sequence to abort.
Sending 200, 100-byte ICMP Echos to 192.168.11.1, timeout is 2 seconds:
Packet sent with a source address of 192.168.6.1
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Success rate is 100 percent (200/200), round-trip min/avg/max = 1/21/50 ms

 

output:

Switch#sh policy-map int gi1/0/48
GigabitEthernet1/0/48

Service-policy output: priority-queue

queue stats for all priority classes:
Queueing
priority level 1

(total drops) 0
(bytes output) 2915622396

Class-map: voice (match-any)
0 packets
Match: dscp ef (46)
0 packets, 0 bytes
5 minute rate 0 bps
Priority: Strict,

Priority Level: 1

Class-map: class-default (match-any)
0 packets
Match: any


(total drops) 13855256
(bytes output) 831113846637
switch#

6 Replies 6

Scott Leport
Level 7
Level 7

Hi,


Does setting the decimal number to 160 work?

https://www.tucny.com/networking/dscp-tos

How about trying an extended traceroute and setting the DSCP value? 

How do I set the tos value with an extended traceroute? Setting the DSCP value instead TOS with ping also did not work.

 

ping switch2 source gi1/0/48 tos 160
Type escape sequence to abort.
Sending 5, 100-byte ICMP Echos to 192.168.11.1, timeout is 2 seconds:
Packet sent with a source address of 10.5.1.5
!!!!!
Success rate is 100 percent (5/5), round-trip min/avg/max = 20/28/40 ms
Switch#sh policy-map int gi1/0/48
GigabitEthernet1/0/48

Service-policy output: priority-queue

queue stats for all priority classes:
Queueing
priority level 1

(total drops) 0
(bytes output) 2923392367

Class-map: voice (match-any)
0 packets
Match: dscp ef (46)
0 packets, 0 bytes
5 minute rate 0 bps
Priority: Strict,

Priority Level: 1

Class-map: class-default (match-any)
0 packets
Match: any


(total drops) 13855256
(bytes output) 837610501010
Switch#

Joseph W. Doherty
Hall of Fame
Hall of Fame

You're pinging on/from the same switch with the policy?

If so, I recall (?) locally source traffic, although properly marked, by default, might be treated "differently" from transit traffic by the interface's egress policy.

Yes I tried pinging from the same switch with the policy. Tried pinging from a down stream switch through switch1 to switch2 too but no luck.

Pinging through the switch, from another switch, should avoid any of the possible locally sourced issues.

Over the years, I have seen bugs in Catalyst 3K switches where "interface" stats aren't correctly updated although packets are processed correctly.

I hadn't noticed before, but . . .

Queueing
priority level 1

(total drops) 0
(bytes output) 2923392367

Class-map: voice (match-any)
0 packets
Match: dscp ef (46)
0 packets, 0 bytes
5 minute rate 0 bps
Priority: Strict,

Priority Level: 1

Hmm, notice you have bytes having been sent PQ 1 by class for that PQ 1 has not packet matches?

What IOS version are you using?

Yes, I noticed the same. 

 

One 3850 has SW image cat3k_caa-universalk9 and SW version 03.07.04E.

 

The other exhibiting the same problem has 

SW Image CAT3K_CAA-UNIVERSALK9 and SW Version 16.3.5b

 

Have not checked out the newer version.