Questions tagged [ping]
Ping is a mechanism to see if a remote host is reachable via an IP network
954
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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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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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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, 10.0....
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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 ...
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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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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): ...
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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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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 ...
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3
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How to Ping explicitly from eth1 instead of eth0
I'm trying to execute a ping with eth1, but the program uses eth0(the default network device). Any tips, tricks, or alternate techniques available?
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How to stop ping output? [closed]
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)
...
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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 ...
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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 (...
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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?
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Why can't I ping my freshly set up amazon web service EC2 instance?
I was following this tut on how to set up a EC2 instance on Ubuntu but qhen trying to execute ssh command on my IP address, I had an operation Timeout.
So I tried to ping it but no chance neither.
...
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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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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 ...
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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 ...
PHP
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votes
1
answer
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Why is ping working when all incoming and outgoing connections are blocked in the firewall?
I have DENIED both incoming and outgoing connections using ufw on Debian VPS. There is only one rule defined, which is to allow connection to SSH port.
ufw is enabled and working.
Yet I am still ...
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how to know who ping my computer ? [duplicate]
Possible Duplicate:
How can I know when my computer is pinged?
I'm using Linux. I would like to know how to tell who is pinging my computer. I have seen this similar question using Windows, but ...
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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 ...
user55029
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6
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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 ...
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Linux command to wait for a SSH server to be up
I have a script which creates a virtual machine and gives me back an IP address.
Then I would like to do something like this:
waitforssh 192.168.2.38 && ssh 192.168.2.38
And it will wait ...
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PING icmp open socket: Operation not permitted in vserver
I am running a vserver environment with several virtual machines. A single VM has the following problem:
$ ping 8.8.8.8
ping: icmp open socket: Operation not permitted
$ ls -l $(which ping)
-rwsr-xr-...
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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 ...
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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 ...
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How can ping know if my host is down
When I ping a server there are two kinds of result I might get:
Timeout
Host is down message
How does the ping command know if a host is down? In both cases, the host does not send any response to ...
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2
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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
...
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5
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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 192....
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How to disable responses to PING [closed]
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?
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I am able to ping a device on a different subnet without passing through a L3 device. How?
I have two devices in the same broadcast domain. My PC and an Avaya IP Control Unit.
My IP is 10.168.10.154/22.
Avaya Device IP is 192.168.10.99/23.
I am able to ping this device and don't ...
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3
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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 ...
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Ping not working from tap interface attached to bridge interface with ip on same subnet as that of bridge to outside
My requirement is to create a multiple tap interfaces, each with ip address on same subnet.
I tried this by creating a bridge
br0 (192.168.1.199)
___________|...
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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 ...
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3
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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 ...
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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!
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Ping with long delay but short reported time
What does it mean when a ping reports a reasonable time (~10ms) but actually takes quite a long wall clock time (~15 seconds)? (Additionally, passing the -U option for "full user-to-user latency" has ...
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Why can't I ssh or ping my brand new Amazon EC2 instance?
I just created a free EC2 instance with all the defaults. It says it's running in the AWS Management Console. On the "Instance Actions" menu, I click "Connect". I copy the DNS name provided (looks ...
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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 ...
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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 ...
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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 ...
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Why echo request doesn't show in tcpdump?
I have two network segments connected using a IPSEC-VPN tunnel :
NET#1: a.b.0.0/16 with LAN gateway a.b.0.1
NET#2: x.y.0.0/16 with LAN gateway x.y.130.1
I initiate a ping from a.b.0.1 to x.y.130.100 ...
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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 ...
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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 ...
user80776
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votes
3
answers
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Why do tracert latencies not add up to ping latency?
One might expect the sum of the tracert latencies to equal 267ms:
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Change how Nagios determines if server is offline?
I'm new to nagios and my server is on a network which does not allow the server to be pinged. Is it possible for me to check if the server is up another way? e.g via SSH or HTTP? How would I do this ...
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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:
C:\Users\...
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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 ...
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4
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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 ...
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Can browse, but can't ping
I am behind a corporate network. I am unable to use git, since it can't resolve server names
fatal: Unable to look up someserver.org (port 9418) (No such host is known. )
I can't ping that server (...
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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 ...
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