We have a problem with our WS-C3560V2-24TS running IOS c3560-ipservicesk9-mz.122-53.SE2.bin.
The equipment keep dropping packets for no apperent reason.
This is what we are seeing:
LAN-port
Router0#sh interfaces fastEthernet 0/2 | include drops:
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 20595
WAN-port
Router#sh interfaces GigabitEthernet0/1 | include drops
Input queue: 0/75/0/0 (size/max/drops/flushes); Total output drops: 2460
Port configuration:
Router#sh running-config interface gigabitEthernet 0/1
Building configuration...
Current configuration : 339 bytes
!
interface GigabitEthernet0/1
description unused
switchport trunk encapsulation dot1q
switchport trunk allowed vlan 3596,3597
switchport mode trunk
bandwidth 1000000
speed nonegotiate
srr-queue bandwidth share 1 19 79 1
srr-queue bandwidth shape 4 0 0 0
srr-queue bandwidth limit 10
priority-queue out
mls qos trust dscp
end
Router#sh running-config interface fastEthernet 0/2
Building configuration...
Current configuration : 168 bytes
!
interface FastEthernet0/2
switchport access vlan 901
switchport mode access
bandwidth 100000
speed 100
duplex full
priority-queue out
mls qos vlan-based
end
QoS/MLS
We have tried to increase the queue-set values to the following:
Router#show mls qos queue-set 1
Queueset: 1
Queue : 1 2 3 4
----------------------------------------------
buffers : 20 40 20 20
threshold1: 400 2000 1500 1500
threshold2: 400 2000 1500 1500
reserved : 100 100 100 100
maximum : 400 2000 1500 1500
But we dont see any improvment.
The QoS/MLS config is as follows:
mls qos map dscp-cos 8 9 10 12 14 16 17 18 to 3
mls qos map dscp-cos 20 22 32 33 34 36 38 48 to 3
mls qos srr-queue output dscp-map queue 1 threshold 1 9 10 12 14
mls qos srr-queue output dscp-map queue 2 threshold 1 17 18 20 22
mls qos srr-queue output dscp-map queue 3 threshold 1 33 34 36 38
mls qos queue-set output 1 threshold 1 400 400 100 400
mls qos queue-set output 1 threshold 2 2000 2000 100 2000
mls qos queue-set output 1 threshold 3 1500 1500 100 1500
mls qos queue-set output 1 threshold 4 1500 1500 100 1500
mls qos queue-set output 1 buffers 20 40 20 20
mls qos
class-map match-all ef.2001
match access-group 2001
class-map match-all af3.ldp.2006
match access-group 2006
class-map match-all df.ldp.2011
match access-group 2011
!
!
policy-map qoslan_vlan901_in
class ef.2001
set dscp ef
class af3.ldp.2006
set dscp af31
class df.ldp.2011
set dscp default
Router#sh ip access-lists 2011
Extended IP access list 2011
10 permit ip any any (518944 matches)
Router#sh ip access-lists 2001
Extended IP access list 2001
10 permit ip any any precedence critical
20 deny ip any any (518944 matches)
Router#sh ip access-lists 2006
Extended IP access list 2006
10 permit ip any any precedence flash
20 deny ip any any (518944 matches)
Interface counters
ti280486534j580#sh interfaces counters errors | include Port|Fa0/2 |Gi0/1
Port Align-Err FCS-Err Xmit-Err Rcv-Err UnderSize OutDiscards
Fa0/2 0 0 0 0 0 20952
Gi0/1 0 0 0 0 0 2460
We are shaping the gig uplink to 100Mbps, the equipment is dropping pakets randomly and not because the shaper kicks in and starts to drop pakets.
We really need some help on how to fix this as we are seeing the same thing on many of our routers.
If we turn off the mls qos the problem goes away so it is definitly connected to the mls qos in some way.
Best regards
Magnus
