Configuring QoS for Vlans

[HP2920-key]

hello everyone,

i need your help,

i need to configure the qos on two switches (hp 2920) to manage the traffic of two Vlans 3 and Vlan 4 :

vlan 3

>> qos priority 5  (low priority) 

vlan 4

>> qos priority 7        ( high priority)

Then i tried to send traffic from vlan 3 and vlan 4 to a computer that belong to both vlan.

from ES3 :   trame=Ether(dst="x....4",src="x....3")/Dot1Q(vlan=4, prio=7)/IP(dst="x.x.x.4")

from ES2 :   trame=Etherr(dst="x....4",src="x....2")/Dot1Q(vlan=3, prio=5)/IP(dst="x.x.x.4")

when i tried to capture the traffic on both virtual interfaces of ES4. they are both received at the sams time, so the priority does not work ???

[HP2920-key]

Here is the last Qos configuration that i apply in my network :

[AbeAbe]

Hi,

are there any congestions?

QoS only kicks in when there are congestions!

hth

Alex

[HP2920-key]

i am sending at the same time frames from two vlans 3 and 4 to the same ES and i received :

from both ES2 (vlan 3 : 10.10.30.2 -> 10.10.30.4)

and ES3 (vlan 4: 10.10.40.3 -> 10.10.40.4)

from scapy.all import *
import time
Asrc="00:00:00:00:00:02"
Adst="00:00:00:00:00:04"

#AFDX traffic
BAG=2
IFG=0.0096
simu=10
nb_periodes=int(simu/BAG)

trame=Ether()/Dot1Q(vlan=3, prio=5)/IP()

pk=Ether(dst=Adst, src=Asrc)/Dot1Q(vlan=3, prio=5)/IP(dst='10.10.30.4',tos=184)
Atime=trame.time
pk=pk/Padding("Debut(ES2)="+str(Atime))
sendp(pk, iface='eth2.3')

date_debut=trame.time

while trame.time < date_debut + simu :
i=0
while i < nb_periodes :
print("----------ES2------------")
trame=Ether(dst=Adst, src=Asrc)/Dot1Q(vlan=3, prio=5)/IP(dst='10.10.30.4',tos=184)
Atime=trame.time
trame=trame/Padding(str(Atime))
print("---------------arrival time du paquet emis----------------")
print("Te(horloge ES2)="+str(Atime))
sendp(trame, iface='eth2.3')
time.sleep( date_debut + (i+1)*BAG - IFG-trame.time)
i=i+1

on the receiver ( using tcpdump):

11:29:12.568922 IP 10.10.40.3 > 10.10.40.4: ip 0
11:29:12.593662 IP 10.10.30.2 > 10.10.30.4: ip 0
11:29:14.565019 IP 10.10.40.3 > 10.10.40.4: ip 0
11:29:14.585764 IP 10.10.30.2 > 10.10.30.4: ip 0
11:29:16.564860 IP 10.10.40.3 > 10.10.40.4: ip 0
11:29:16.589601 IP 10.10.30.2 > 10.10.30.4: ip 0
11:29:18.565452 IP 10.10.40.3 > 10.10.40.4: ip 0
11:29:18.589690 IP 10.10.30.2 > 10.10.30.4: ip 0
11:29:20.565043 IP 10.10.40.3 > 10.10.40.4: ip 0
11:29:20.581788 IP 10.10.30.2 > 10.10.30.4: ip 0

i want to visualize the reception with priority of traffic of vlan 4

[parnassus]

Are those packets sent really at the same time? if so then it seems that the one destined to VLAN4 (10.10.40.4) arrives before the one destined to VLAN3 (10.10.30.4), the time difference looks of tenths of a second...between each pair of different packets.