7700 ping with packet drops but interfaces do not have error

[davidpcm]

Please advice, ping from core switch 172.18.159.226 from datacenter to remote core switch 172.18.159.230, packet drops observed, but no errors on interface. Please help, thanks!

From 172.18.159.230:

64 bytes from 172.18.128.25: icmp_seq=216. time=23. ms
64 bytes from 172.18.128.25: icmp_seq=217. time=15. ms
----172.18.128.25 PING Statistics----
218 packets transmitted, 218 packets received, 0% packet loss
round-trip (ms) min/avg/max = 13/20/196

-> show interfaces
Slot/Port 1/1 :
Operational Status : up,
Last Time Link Changed : SUN JUN 18 15:24:06 ,
Number of Status Change: 1,
Type : Ethernet,
MAC address : 00:d0:95:c5:a8:f2,
BandWidth (Megabits) : 1000, Duplex : Full,
Autonegotiation : 1 [ 1000-F ],
Long Accept : Enable, Runt Accept : Disable,
Long Frame Size(Bytes) : 10240, Runt Size(Bytes) : 64,
Rx :
Bytes Received : 794248747620, Unicast Frames : 882898624,
Broadcast Frames: 11603504, M-cast Frames : 5152649,
UnderSize Frames: 0, OverSize Frames: 0,
Lost Frames : 0, Error Frames : 0,
CRC Error Frames: 0, Alignments Err : 0,
Tx :
Bytes Xmitted : 308796894822, Unicast Frames : 739622614,
Broadcast Frames: 3395301, M-cast Frames : 2990113,
UnderSize Frames: 0, OverSize Frames: 0,
Lost Frames : 2, Error Frames : 0,
Collided Frames : 0

#####

From 172.18.159.226:

[T] 64 bytes from 172.18.159.230: icmp_seq=56. time=1907. ms
[T] 64 bytes from 172.18.159.230: icmp_seq=57. time=1138. ms
64 bytes from 172.18.159.230: icmp_seq=58. time=195. ms
----172.18.159.230 PING Statistics----
60 packets transmitted, 59 packets received, 1.67% packet loss
round-trip (ms) min/avg/max = 69/1104/2846

Slot/Port 1/4 :
Operational Status : up,
Last Time Link Changed : TUE JUN 27 13:37:08 ,
Number of Status Change: 1,
Type : Ethernet,
MAC address : 00:d0:95:c5:a7:1d,
BandWidth (Megabits) : 1000, Duplex : Full,
Autonegotiation : 1 [ 1000-F ],
Long Accept : Enable, Runt Accept : Disable,
Long Frame Size(Bytes) : 10240, Runt Size(Bytes) : 64,
Rx :
Bytes Received : 5980360408265, Unicast Frames : 18743705423,
Broadcast Frames: 193973205, M-cast Frames : 84783022,
UnderSize Frames: 0, OverSize Frames: 0,
Lost Frames : 0, Error Frames : 0,
CRC Error Frames: 0, Alignments Err : 0,
Tx :
Bytes Xmitted : 19654176345167, Unicast Frames : 21919106082,
Broadcast Frames: 366874886, M-cast Frames : 99969717,
UnderSize Frames: 0, OverSize Frames: 0,
Lost Frames : 1, Error Frames : 0,
Collided Frames : 0