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Questions tagged [ping]

A tool commonly used to test the reachability of a given host, either on the internet or in a local network.

ping works by sending ICMP packets to the target host and timing the host's response. It also measures connection quality by recording percentage packet loss. The time taken to establish the connection is not taken into account, only the time it takes for the packets themselves to be transferred.

On *nix machines, ping can be run by simply executing

ping example.com

ping also has a partner-in-crime utility - ping6. ping6 essentially works the exact same way as ping, but it uses an IPv6 stack instead of an IPv4 stack. This means that it expects IPv6 addresses, IPv6 DNS records, and will use IPv6 to transfer the ICMP packets.

Both binaries are provided by the iputils package on most of GNU/Linux distributions. Pinging a host known to always respond correctly (such as 8.8.8.8 - one of Google's Public DNS servers) is a common first step in diagnosing network issues.

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What could DUP mean when using ping?

What could DUP mean when using ping?
LanceBaynes
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-m option does not work in ping command

I was learning the Linux ping command and its options, and read about the -m option which is used to mark the outgoing packet. When receiving, we can filter that marked packet result first. I am trying to set the mark for the packet, but I got a…
user152030
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Why doesn't “ping -l” works when ping works?

I can ping ping AddressIp 64 bytes from indirizzoIp: icmp_req=1 ttl=42 time=149 ms but with additionnal parameter ping AddressIp -l 1400 ping: cannot set preload to value > 3 ping AddressIp -t -l 1400 ping: can't set unicast time-to-live:…
Aldo
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ping statistics time meaning

# ping -c 3 amsterdam.voip.ms PING amsterdam.voip.ms (37.58.88.242) 56(84) bytes of data. 64 bytes from f2.58.3a25.ip4.static.sl-reverse.com (37.58.88.242): icmp_seq=1 ttl=52 time=98.5 ms 64 bytes from f2.58.3a25.ip4.static.sl-reverse.com…
No_name
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Why am I getting DUP! reply when using ping -A

We have 2 VM's running on ESX 5.1. When I do a ping -A, after a while I get every second ping as a DUP!. When doing a normal ping, I get 5 or 6 DUP!s, and then it returns to normal. Any ideas what to check?
Dion
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Ping with negative time

Today I've test my connection and after some hours the result is the following --- 8.8.8.8 ping statistics --- 19482 packets transmitted, 19092 packets received, 2.0% packet loss round-trip min/avg/max/stddev = -164.144/75.413/1752.758/100.035…
alessandro308
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Continues Pinging to background, save logs and show statistics

I'm trying to make a script that save the ping logs to .txt or .log file. To monitor if my connection is intermittent or not, I'm using this script: $nohup ping 8.8.8.8 > timeout.txt & Then when I check if its pinging: $tailf timeout.txt It's…
oacebes
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Why does the `ping -W` flag not timeout if the connection is down?

On Debian Buster, judging by the description of the -W flag to ping, I assumed that I could use something like: ping -i 10 -W 5 8.8.8.8 to continuously monitor an Internet connection. If the connection goes down I would expect that 5 seconds after…
Heath Raftery
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hping3 reports higher latency than ping

I'm just checking the network latency with different tools e.g. with hping3: sudo hping3 -A -n -p 80 www.google.ro HPING www.google.ro (ppp0 172.217.20.3): A set, 40 headers + 0 data bytes len=40 ip=172.217.20.3 ttl=59 id=14578 sport=80 flags=R…
Adrian
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Does ping validate icmp checksum?

ICMP messages contain checksums: https://www.rfc-editor.org/rfc/rfc792 Does ping validate the checksums when receiving an echo reply message? I don't see a note about it in the man page. I'm using Fedora 27.
FGreg
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How to interpret ping output

Since 3 days ago I can not open (from outside Brazil) the site UOL. First I thought it could be off line. But 3 days! It is a very big Internet web site and host. I tried with FF and Google, but nothing. Then I decided to try ping www.uol.com.br and…
Sigur
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Why ping an IP is different to ping a website?

I've noticed a strange behaviour (at least, I can't get out). Ping IP, specifying packet size: ping -s 128 8.8.8.8 I get: PING 8.8.8.8 (8.8.8.8) 128(156) bytes of data. 72 bytes from 8.8.8.8: icmp_req=1 ttl=43 (truncated) Ping website,…
Luca Davanzo
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Unable to ping the IP during first boot

I am trying to add some routes in /etc/init.d/S98 script but it is failing to ping the gateway IP and hence route addition is failing. But once all the S98 scripts are executed I am able to ping the IP and add the routes. Below are the logs captured…
Puneeth
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Why doesn't "ping -vrf" works when ping works?

0:root@SERVER:/root # ping IPADDRESS PING IPADDRESS (IPADDRESS): 56 data bytes 64 bytes from IPADDRESS: icmp_seq=0 ttl=254 time=0 ms 64 bytes from IPADDRESS: icmp_seq=1 ttl=254 time=0 ms 64 bytes from IPADDRESS: icmp_seq=2 ttl=254 time=0 ms ^C ---…
gasko peter
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Why does some line in result of ping include hostname?

PING (ip) 56(84) bytes of data. 64 bytes from (ip): icmp_seq=1 ttl=116 time=22.3 ms 64 bytes from (ip): icmp_seq=1 ttl=116 time=22.3 ms (hostname) 64 bytes from (ip): icmp_seq=1 ttl=116 time=22.3 ms (hostname) 64 bytes from (ip): icmp_seq=1…
Bùi Quang Nam
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