Ping drop with size 9000

[ahmads143]

Hi All,
I am facing one issue and thought you guys can throw some light on it.

R1 and R2 is 7705 SAR-8 and newly integrated in my network and connected with R3 and R4 and after that cloud.
I wanted to ping one ip 10.xx.xx.1 with size 9000 from router 1 and router 2 both.

output:
R1 :---> No drop with size 9000
R2:---> intermittent drop with size 9000 and working ok with 1518

I have tried to ping from R2 to R4 wan IP with size 9000 and was working ok..No drop.

My config details of wan ports(10G) are

R2:
port 1/1/5
ethernet
mode network
encap-type dot1q
mtu 9212
network
queue-policy "6COS"
exit
lldp
dest-mac nearest-bridge
admin-status tx-rx
notification
tx-tlvs port-desc sys-name sys-desc sys-cap
tx-mgmt-address system
exit
dest-mac nearest-non-tpmr
admin-status tx-rx
notification
tx-tlvs port-desc sys-name sys-desc sys-cap
tx-mgmt-address system
exit
exit
egress-rate 10000000
exit
no shutdown

And R4 Port config

R4:> port 1/1/5
ethernet
encap-type dot1q
egress-scheduler-policy "NW:21xSTM:SCHEDULER"
crc-monitor
sd-threshold 2 multiplier 2
window-size 5
exit
network
queue-policy "6COS"
accounting-policy 70
collect-stats
exit
lldp
dest-mac nearest-bridge
admin-status tx-rx
notification
tx-tlvs port-desc sys-name sys-desc sys-cap
tx-mgmt-address system
exit
dest-mac nearest-non-tpmr
admin-status tx-rx
notification
tx-tlvs port-desc sys-name sys-desc sys-cap
tx-mgmt-address system
exit
exit
exit
no otu
no shutdown
exit

Please see my network topology for reference in the attachment.(Attachment has no virus )


R1-----------R2
1/1/5 | | 1/1/5
| |
| |
1/1/5 | | 1/1/5
R3------------R4
| |
| |
10.xx.xx.1


Can you please suggest me what is the issue in it..