Ping is a mechanism to see if a remote host is reachable via an IP network

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227
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Ping a Specific Port

Just a quick sanity check here. Can you ping a specific port of a machine, and if so, can you provide an example? I'm looking for something like ping ip address portNum.
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12answers
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Is Ping a reliable way to check if a server is available?

In my application I am pinging a server and waiting for a response. I am using this to determine whether the server is available and responsive or not. Is this a reliable way of determining ...
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8answers
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What does “TTL expired in transit” mean on a ping attempt?

We get the message “TTL expired in transit” when we try to ping to a server in a different network segment. When we run tracert, 4 ip addresses repeat themselves indefinitely: 14 60 ms 59 ms ...
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votes
5answers
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Why do we ping the IP 4.2.2.2 to test connectivity?

For as long as I can remember, I've always used the IP 4.2.2.2 when testing network connectivity using ping. What is significant about this IP, and when did this practice start?
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2answers
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Pinging an IP address responds with different IP

When I try to ping the IP address 10.10.208.57 I have no response since nothing exist in the network with that IP address. However if I try to ping 10.10.208.057 instead another IP address responds: ...
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6answers
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Enable Ping in Windows Server Firewall?

I've just installed Windows Server 2008 on a server and I'm able to connect through Remote Desktop but can't ping. Do I need to open an special port on the firewall to be able to ping a server?
16
votes
8answers
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Is there any way to ARP ping on Windows?

On Linux and other systems, there is an utility called arping which can be used to send ARP requests ("pings") and show the answers, much like the "ping" utility but using ARP instead of ICMP. Is ...
14
votes
12answers
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Will a higher bandwidth Internet connection lower ping response time?

It sounds obvious that a faster connection lowers latency... But I wonder: I am working remotely on a host the other side of the world - light can only travel so fast (1 foot in a nano second) and we ...
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3answers
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What does mdev mean in ping(8)?

What does mdev mean in ping output (last row below)? me@callisto ~ % ping -c 1 example.org PING example.org (192.0.43.10) 56(84) bytes of data. 64 bytes from 43-10.any.icann.org (192.0.43.10): ...
12
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2answers
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Strange: why does linux respond to ping with ARP request after last ping reply?

I (and a colleague) have just noticed, and tested, that when a Linux machine is pinged, after the last ping it initiates a unicast ARP request to the machine that initiated the ICMP ping. When pinging ...
10
votes
9answers
21k views

How to ping in linux until host is known?

How can I ping a certain address and when found, stop pinging. I want to use it in a bash script, so when the host is starting up, the script keeps on pinging and from the moment the host is ...
10
votes
9answers
5k views

How to disable responses to PING

I feel like this should be a really simple thing to do, but googling and checking SF I didn't see anything. I'm trying to make my Fedora server not respond to pings, how do I do that?
10
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7answers
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How can I set a short timeout with the ping command?

I am trying to write a script that lists all the hosts on my LAN (there a about 20 of them) and writes the ping status next to each host. I have the DHCP leases file, so I have all the IPs (say, ...
10
votes
3answers
11k views

Why can't I ssh into (or even ping) my Ubuntu VM from the Mac OS X host?

I'm running Ubuntu 8.04 as a virtual machine using VMware Fusion 3.0 on Mac OS X 10.5.8. I want to be able to ssh into my VM from the Mac OS X host (so I can use MacFUSE and SSHFS to mount the VM's ...
9
votes
6answers
20k views

How does ping know that my packets are filtered?

I'm customer of an Irish ISP, eircom, which has started censoring the pirate bay. When I try to ping 194.71.107.15 which is the IP address of thepiratebay.com, I get this output: PING 194.71.107.15 ...
9
votes
4answers
1k views

Ping replacement that shows real time

Is there a ping replacement that will display the system's date/time in addition to the round trip time and sequence number? I would prefer a tool that runs on Linux, but if there is a cli tool I can ...
9
votes
1answer
36k views

How to stop ping output?

I run ping <hostname> command in console and it now outputs hundreds of those rows now (icmp_seq=526 ttl=64 time=0.026 ms), icmp_seq is like 500 or more now. How to stop it? (linux debian) ...
9
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6answers
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Why does traceroute take much longer than ping?

How to explain this? C:\Documents and Settings\Administrator>tracert google.com Tracing route to google.com [64.233.189.104] over a maximum of 30 hops: 1 <1 ms <1 ms <1 ms ...
9
votes
4answers
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Linux router: ping doesn't route back

I have a Debian box which I'm trying to set up as a router and an Ubuntu box which I'm using as a client. My problem is that when the Ubuntu client tries to ping a server on the Internet, all the ...
8
votes
6answers
10k views

Network latency: 100Mbit vs. 1Gbit

I have a webserver with a current connection of 100Mbit and my provider offers an upgrade to 1Gbit. I understand that this refers to throughput but the larger the packets, the faster they can be ...
8
votes
8answers
14k views

OS X: Can't Resolve Windows Machine Names

I'm running a mixed environment at home and at work. My server machines are Win Vista, and I have a Unibody Macbook Pro running 10.5.7 On my mac, I can ping some home windows by name (If I use the ...
8
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2answers
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Data obtained from ping: is it round trip or one way?

I have 2 servers, each in two separate locations. I need to host an application on one, and the database server on the other. From the app server, if I ping the database server, on average I get ...
8
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2answers
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DNS can't resolve hostname; nslookup can

I have a user on Windows 7 that is trying to access a local server with a DNS name of windows.cs. We have two internal DNS servers. The DHCP server assigns users the two internal DNS servers as ...
8
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4answers
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How does TCP Ping or Traceroute Work?

How does the tcp ping or traceroute work? Does it take in account just the time it takes to establis the TCP handshake? Also in ICMP ping you can specify the packet size, can this be achieved in TCP ...
8
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2answers
1k views

Public hosts for ping

For my firewall scripts to determine whether my ISP is up I need a few reliable, geographically distributed addresses to ping. I could just use some major sites like Google, Akamai, etc. But that ...
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5answers
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Ping “replies” from same computer with 'Destination host unreachable' (no route to other computer)

I've got two computers in a LAN behind a wireless router. One has XP with ip 192.168.1.2 This one has W7 with ip 192.168.1.7 If I try to ping the other one from this computer, I get this: ...
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14answers
15k views

How can I determine if a machine is online without using ping?

I used to use an application that could ping or maybe run a port scan on a machine even if the machine was configured to not allow it. I am currently trying to ping a remote machine on our WAN, but I ...
6
votes
1answer
375 views

ping with line numbers

Simple question: how to make ping on Linux to show line numbers in output? I mean: 1 64 bytes from www.site.com (2.7.1.1): icmp_req=1 ttl=247 time=17.9 ms 2 64 bytes from www.site.com (2.7.1.1): ...
6
votes
3answers
5k views

Find information for local IP address?

We have had a BT engineer visit recently, trying to solve a problem with our IP phone system. One point they made was that we had four DHCP servers running on the network. I have disabled two of them ...
6
votes
3answers
1k views

Why would ping give me fast rtt values, but take a long time for each response to come back?

I've got a bit of a basic networking question here regarding ping. When pinging a particular host on a completely different subnet, I get a response like this: PING myhost.example.com (1.2.3.4) ...
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3answers
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Why is ping to Google servers and Google DNS so low?

I noticed that ping to Google DNS and to google.com from Serbia is about 15ms, but google servers are located in California! http://www.geoiptool.com/en/?IP=173.194.39.110 My dedicated server is ...
5
votes
1answer
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My server is working fine, but I can't ping it

I noticed earlier, one (of many) of our EC2 instances doesn't respond to ping requests. Everything else runs fine, SSH, HTTP, FTP, Database all working perfectly, but ping fails. This instance is ...
5
votes
2answers
5k views

Nagios bizare ping behaviour

I have nagios setup as I want it, but last night it started alerting me of a problem pinging the internet. (I have a check that pings www.google.com to test that the internet is still working) Now ...
5
votes
2answers
357 views

Why nslookup doesn't use mdns while ping do?

In dnsmasq.conf: address=/local/127.0.0.1 In resolv.conf: # Generated by NetworkManager domain example.com search example.com nameserver 127.0.0.1 nameserver 10.66.127.17 nameserver 10.68.5.26 I ...
5
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2answers
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Pings from VPN network to VPN client work; pings into from VPN client to VPN network fail - why?

We are in the process of setting up an OpenVPN server for some servers running in a cloud. We are stumped with a connectivity problem whereby the hosts on the VPN server's LAN can ping te VPN client, ...
5
votes
1answer
7k views

IPv6: Can't ping anything - “Operation not permitted”

I've been working on getting IPv6 support into my network, and had everything working properly for a short while. The server is running Ubuntu Server 8.10. Now however whenever I attempt to do ...
5
votes
2answers
4k views

nmap does not find alive hosts with ping scan

I try to ping scan my local network using nmap, but it doesn't seem to find machines that are for sure alive. It responses to ping but on to ping scan. Results for ping: $ ping 192.168.0.2 PING ...
4
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2answers
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Unable to ping, although can download packages

I've installed Debian Squeeze on a Dell PowerEdge server. However, I'm facing some problem with configuring the network. Although I can ping machines inside my network, I'm unable to d0 so outside the ...
4
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2answers
751 views

Why do tracert latencies not add up to ping latency?

One might expect the sum of the tracert latencies to equal 267ms:
4
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1answer
3k views

What do the RTT numbers mean in a TraceRoute result?

I have this traceroute result, and I am wondering what EXACTLY do the 3 numbers mean at the end of each line? I assume they are ping times, but what exactly is the difference between each number? 1 ...
4
votes
3answers
13k views

Ping from specific network adapter on Windows

Hey, I've been troubleshooting network issues on servers with 2 NICs and laptops with wired and wireless cards. How can I force the PING and TELNET to be sent from a specific adapter? I know it's a ...
4
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2answers
5k views

How can I know when my computer is pinged?

I am trying to find a problem on a local network. I want to be able to know when a specific computer (Windows XP) is pinged. Thanks!
4
votes
3answers
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ping -f shows problems but regular ping doesn't

I have a strange issue, hosting at Softlayer Washington data center. Test from an EC2 instance to my server at Softlayer :- [root@EC2-box ~]# ping -f -c 100 MY-SL-BOX PING MY-SL-BOX (MY-SL-BOX) ...
4
votes
2answers
579 views

Faster way to ping URL than curl [closed]

What would be the fastest way to check whether the specified URL is working? (responding in OK http status code)? For now I'm using curl, but I have bunch of URLs to test in a loop, so I'm looking ...
4
votes
1answer
624 views

tcpdump on interface when pinging nonexistent hosts on local network

I've statically configured the IP address of an interface on a server: ip addr add 10.40.0.6/16 broadcast 10.40.255.255 dev eth1 If I try to ping a machine on the network (e.g., 10.40.0.1), it ...
4
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2answers
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Cannot ping over LAN until a ping is received

I have two OSX machines on a local subnet. Pings from Machine A to Machine B consistently timeout until Machine B pings Machine A. After B pings A, A can successfully ping B, but this success is ...
4
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1answer
471 views

How can I use ping with a large packet size to troubleshoot network issues?

What types of network problems can be identified with ping of a large packet size?
4
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7answers
2k views

Scan for connected, powered on computers on a network?

I want to scan for powered on computers on my LAN and gather logs about that. I tried nmap but it didn't work very well (a lot of switched on computers are not getting detected). nmap -sP ...
4
votes
2answers
665 views

what does `pipe <number>` mean in `ping` output?

While running a test to diagnose some alleged network problem, I got this output from ping: --- r01c01b11n02 ping statistics --- 30000 packets transmitted, 29995 received, 0% packet loss, time 6309ms ...
4
votes
4answers
14k views

Graphical Ping utility with logging

I need to continuously test the quality of the connection between hosts, and I would like to use ping for that, in order to see WHEN the problem occurs. It should provide LOG of the pinging, with ...