Ping timeout issues [closed] - linux

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Good afternoon,
I'm working on a three computers (under Linux Mint 14) LAN. They are connected to a switch and none of them have any firewall.
The problem is that each one of them is really slow to detect failures of one of their peers.
For example, I proceed to that test :
I ping from 192.168.0.2 to 192.168.0.3. After 10 seconds, I unplung 192.168.0.3 from the switch... the problem is that 192.168.0.2 takes 48 seconds to detect that !
Here you'll finds logs of that test
oneadmin#192.168.0.2 ~ $ ping -v -i 1 192.168.0.3
PING 192.168.0.3 (192.168.0.3) 56(84) bytes of data.
64 bytes from 192.168.0.3: icmp_req=1 ttl=64 time=0.233 ms
64 bytes from 192.168.0.3: icmp_req=2 ttl=64 time=0.236 ms
64 bytes from 192.168.0.3: icmp_req=3 ttl=64 time=0.220 ms
64 bytes from 192.168.0.3: icmp_req=4 ttl=64 time=0.229 ms
64 bytes from 192.168.0.3: icmp_req=5 ttl=64 time=0.233 ms
64 bytes from 192.168.0.3: icmp_req=6 ttl=64 time=0.210 ms
64 bytes from 192.168.0.3: icmp_req=7 ttl=64 time=0.271 ms
64 bytes from 192.168.0.3: icmp_req=8 ttl=64 time=0.273 ms
64 bytes from 192.168.0.3: icmp_req=9 ttl=64 time=0.291 ms
64 bytes from 192.168.0.3: icmp_req=10 ttl=64 time=0.201 ms
From 192.168.0.2 icmp_seq=58 Destination Host Unreachable
From 192.168.0.2 icmp_seq=59 Destination Host Unreachable
From 192.168.0.2 icmp_seq=60 Destination Host Unreachable
From 192.168.0.2 icmp_seq=61 Destination Host Unreachable
From 192.168.0.2 icmp_seq=62 Destination Host Unreachable
From 192.168.0.2 icmp_seq=63 Destination Host Unreachable
From 192.168.0.2 icmp_seq=64 Destination Host Unreachable
From 192.168.0.2 icmp_seq=65 Destination Host Unreachable
From 192.168.0.2 icmp_seq=66 Destination Host Unreachable
From 192.168.0.2 icmp_seq=67 Destination Host Unreachable
From 192.168.0.2 icmp_seq=68 Destination Host Unreachable
From 192.168.0.2 icmp_seq=69 Destination Host Unreachable
What shall I do to reduce that time?
Best regards,
Sonsolès

Answer 1

You can use -w to specify timeout
ping -c1 -w1 192.168.0.3
Options Details:
-c count
Stop after sending count ECHO_REQUEST packets. With deadline option, ping
waits for count ECHO_REPLY packets, until the timeout expires.
-w deadline
Specify a timeout, in seconds, before ping exits regardless of how many pack‐
ets have been sent or received. In this case ping does not stop after count
packet are sent, it waits either for deadline expire or until count probes
are answered or for some error notification from network.

Answer 2

I guess you can you -O
ping -O host.com
claudionei#TI-03 ~ $ ping -O 10.251.15.251
PING 10.251.15.251 (10.251.15.251) 56(84) bytes of data.
64 bytes from 10.251.15.251: icmp_seq=1 ttl=62 time=4.50 ms
no answer yet for icmp_seq=2
64 bytes from 10.251.15.251: icmp_seq=2 ttl=62 time=1950 ms
no answer yet for icmp_seq=3
64 bytes from 10.251.15.251: icmp_seq=3 ttl=62 time=1409 ms
64 bytes from 10.251.15.251: icmp_seq=4 ttl=62 time=576 ms
64 bytes from 10.251.15.251: icmp_seq=5 ttl=62 time=654 ms
64 bytes from 10.251.15.251: icmp_seq=6 ttl=62 time=4.41 ms
--- 10.251.15.251 ping statistics ---
6 packets transmitted, 6 received, 0% packet loss, time 5001ms
rtt min/avg/max/mdev = 4.416/766.491/1950.291/710.053 ms, pipe 2