Can anyone explain this ?

Amitay B Isaacs (amitay@cse.iitb.ernet.in)
Tue, 18 Mar 1997 14:09:41 +0530


Hi,

I have been getting very weird responses for ping. Here is the ping
output on 2 of the machines.

Script started on Tue Mar 18 14:04:23 1997

amitay@anamika:~$ cat /proc/version
Linux version 2.1.29 (root@varun.cse.iitb.ernet.in) (gcc version 2.7.2) #5 Thu Mar 13 23:43:45 IST 1997

amitay@anamika:~$ ping ftp.cc.iitb.ernet.in
PING ftp.cc.iitb.ernet.in (144.16.106.173): 56 data bytes
64 bytes from 144.16.106.173: icmp_seq=0 ttl=62 time=-21.-2 ms
64 bytes from 144.16.106.173: icmp_seq=1 ttl=62 time=36.2 ms
64 bytes from 144.16.106.173: icmp_seq=2 ttl=62 time=40.0 ms
64 bytes from 144.16.106.173: icmp_seq=3 ttl=62 time=-1.-8 ms
64 bytes from 144.16.106.173: icmp_seq=4 ttl=62 time=44.2 ms
64 bytes from 144.16.106.173: icmp_seq=5 ttl=62 time=2.5 ms
64 bytes from 144.16.106.173: icmp_seq=6 ttl=62 time=2.4 ms
64 bytes from 144.16.106.173: icmp_seq=7 ttl=62 time=33.8 ms
64 bytes from 144.16.106.173: icmp_seq=8 ttl=62 time=2.6 ms
64 bytes from 144.16.106.173: icmp_seq=9 ttl=62 time=-11.-5 ms
64 bytes from 144.16.106.173: icmp_seq=10 ttl=62 time=-24.-1 ms
64 bytes from 144.16.106.173: icmp_seq=11 ttl=62 time=-3.-4 ms
64 bytes from 144.16.106.173: icmp_seq=12 ttl=62 time=37.1 ms
64 bytes from 144.16.106.173: icmp_seq=13 ttl=62 time=0.0 ms
64 bytes from 144.16.106.173: icmp_seq=14 ttl=62 time=32.0 ms
64 bytes from 144.16.106.173: icmp_seq=15 ttl=62 time=-10.-7 ms
64 bytes from 144.16.106.173: icmp_seq=16 ttl=62 time=39.1 ms
64 bytes from 144.16.106.173: icmp_seq=17 ttl=62 time=1.7 ms
64 bytes from 144.16.106.173: icmp_seq=18 ttl=62 time=-1.-5 ms
64 bytes from 144.16.106.173: icmp_seq=19 ttl=62 time=41.6 ms
64 bytes from 144.16.106.173: icmp_seq=20 ttl=62 time=3.0 ms
64 bytes from 144.16.106.173: icmp_seq=21 ttl=62 time=32.8 ms
64 bytes from 144.16.106.173: icmp_seq=22 ttl=62 time=-12.-9 ms
64 bytes from 144.16.106.173: icmp_seq=23 ttl=62 time=0.1 ms
64 bytes from 144.16.106.173: icmp_seq=24 ttl=62 time=29.9 ms
64 bytes from 144.16.106.173: icmp_seq=25 ttl=62 time=2.7 ms
64 bytes from 144.16.106.173: icmp_seq=26 ttl=62 time=20.3 ms
64 bytes from 144.16.106.173: icmp_seq=27 ttl=62 time=1.4 ms
64 bytes from 144.16.106.173: icmp_seq=28 ttl=62 time=2.7 ms

--- ftp.cc.iitb.ernet.in ping statistics ---
29 packets transmitted, 29 packets received, 0% packet loss
round-trip min/avg/max = -24.-1/11.0/44.2 ms

amitay@mitra:~$ cat /proc/version
Linux version 2.0.28 (root@mitra.cse.iitb.ernet.in) (gcc version 2.7.2) #2 Wed Jan 22 22:45:53 IST 1997

amitay@mitra:~$ ping ftp.cc.iitb.ernet.in
PING ftp.cc.iitb.ernet.in (144.16.106.173): 56 data bytes
64 bytes from 144.16.106.173: icmp_seq=0 ttl=62 time=3.6 ms
64 bytes from 144.16.106.173: icmp_seq=1 ttl=62 time=2.0 ms
64 bytes from 144.16.106.173: icmp_seq=2 ttl=62 time=2.1 ms
64 bytes from 144.16.106.173: icmp_seq=3 ttl=62 time=2.0 ms
64 bytes from 144.16.106.173: icmp_seq=4 ttl=62 time=2.1 ms
64 bytes from 144.16.106.173: icmp_seq=5 ttl=62 time=2.1 ms
64 bytes from 144.16.106.173: icmp_seq=6 ttl=62 time=2.4 ms
64 bytes from 144.16.106.173: icmp_seq=7 ttl=62 time=2.2 ms
64 bytes from 144.16.106.173: icmp_seq=8 ttl=62 time=1.9 ms
64 bytes from 144.16.106.173: icmp_seq=9 ttl=62 time=1.9 ms
64 bytes from 144.16.106.173: icmp_seq=10 ttl=62 time=2.4 ms
64 bytes from 144.16.106.173: icmp_seq=11 ttl=62 time=2.1 ms
64 bytes from 144.16.106.173: icmp_seq=12 ttl=62 time=2.3 ms
64 bytes from 144.16.106.173: icmp_seq=13 ttl=62 time=2.2 ms
64 bytes from 144.16.106.173: icmp_seq=14 ttl=62 time=2.2 ms
64 bytes from 144.16.106.173: icmp_seq=15 ttl=62 time=2.1 ms
64 bytes from 144.16.106.173: icmp_seq=16 ttl=62 time=2.1 ms
64 bytes from 144.16.106.173: icmp_seq=17 ttl=62 time=2.1 ms
64 bytes from 144.16.106.173: icmp_seq=18 ttl=62 time=2.3 ms

--- ftp.cc.iitb.ernet.in ping statistics ---
19 packets transmitted, 19 packets received, 0% packet loss
round-trip min/avg/max = 1.9/2.2/3.6 ms

Script done on Tue Mar 18 14:05:41 1997

With 2.0.28 kernel I get a steady ping response while with 2.1.29 kernel
I get some negative (?) times.

Amitay.

---
Courage is resistance to fear, mastery of fear, not absence of fear. - Mark
Twain