Initial Ping Response is a bit high ?

[srikanth ath]

Hello expert,

I was put up with a strange question by my lead and i couldnt reply him back. Could you please help me out.

The destination im trying to rach is only 2 hops away. The First ping response took 25ms , second and further responses are only 1ms, why there is a delay in the first response of the ping ? and  by this inturn affecting the total 5 ping response average to 6ms ?

Please find below with the Ping and Traceroute.

C:\Users\srikanth.athelly>ping 10.24.24.2

Pinging 10.24.24.2 with 32 bytes of data:
Reply from 10.24.24.2: bytes=32 time=25ms TTL=255
Reply from 10.24.24.2: bytes=32 time<1ms TTL=255
Reply from 10.24.24.2: bytes=32 time<1ms TTL=255
Reply from 10.24.24.2: bytes=32 time<1ms TTL=255

Ping statistics for 10.24.24.2:
    Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
Approximate round trip times in milli-seconds:
    Minimum = 0ms, Maximum = 25ms, Average = 6ms

C:\Users\srikanth.athelly>tracert 10.24.24.2

Tracing route to 10.24.24.2 over a maximum of 30 hops

  1     6 ms    <1 ms    <1 ms  10.24.64.3
  2    <1 ms    <1 ms    <1 ms  10.24.24.2

Trace complete.

[devils_advocate]

Run wireshark on one for the PC's and run the ping again, see what the packets say.

[srikanth ath]

Topology

PC -----> L2Switch------->L3Core (10.24.24.2)---------->Internet

From PC to 10.24.24.2 the first Ping response is high/

i will run the wireshark and produce the log file here.

Thanks,

[Richard Michael]

Srikant,

what platform is this?

Richard

[srikanth ath]

Cisco devices  2960, 6500 series switches..

1.Can you say me what are the possibilities which would affect computer to behave in this odd way. that too only first ping jumps to high value.

2. the ping from L2switch to Core switch is good. the first hop looks fine too. the CPU process is not more than 10% in core and L2 switches. What would be the points i should consider in troubleshooting this in the perspectivies of cisco switches.

Thanks,

[Richard Michael]

From the switch perspective the ping packets are processed in CPU whether it is to the switch or from the switch.If you dont have high CPU the next thing that you need to check  Take simultaneous captures on the switch and at the PC. Observe if you see the ping packets and see if there is any delay. To me this looks like some kind of malware effects in the PC. Try to check if you have any anti-virus program running. Disable everything and run it again. Hope there is no DNS resolve too

Richard

[srikanth ath]

Oh thanks, Richard will collect some logs and see what it says.