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

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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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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 ...
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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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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) ...
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1answer
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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 ...
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512 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?
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Need to understand : ping

I am using ubuntu 13.10 and I have used ping before to check server is up/down. Can someone help me understand, as I'm unable to find anything explaining this I did the usual ping command ping ...
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4answers
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how to check connectivity to server by windows tools?

I need to check if client can connect to server on specific TCP port. Server is listening on it. Tried "telnet server_IP port" but telnet is stuck when I see that it's connected to the server. Seems ...
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VirtualBox bridged adapter can ping but can't curl

There is a delicate server running Ubuntu Server 12.04.2. There are 4 useable IPs for this server: A, B, C, D. The server itself takes A. The server is now running two VirtualBox guests, both with ...
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7answers
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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 ...
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2answers
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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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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) ...
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Linux ping command exits early due to ICMP host unreachable

An automated script runs shutdown -r now on a machine, and after a 30s delay, uses ping to determine when the machine is available. I've recently switched the OS from Centos 5 to Oracle Linux 6 and ...
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3answers
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able to dig a hostname but doesn't resolve via ssh or ping

I am using Snow Leopard and cannot ping or ssh into a host but am able to dig: dig some.value.host.com When the ip address comes back in the answer section, then I am able to ssh via ip address ( ...
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1answer
466 views

DNS and PING failure - Windows 2003 DNS and SonicWall NSA240

I am hoping someone can shed some light on this one... I have two Windows 2003 DC's - both running DNS, there are several Windows 2008 R2 and one Windows 2012 Standard server running as member ...
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1answer
912 views

ping: sendmsg: Operation not permitted (sometimes)

On a Ubuntu 14.04 running Haproxy, after a service haproxy reload, Haproxy is suddenly reporting all servers behind it as down. After some digging around, I noticed that ping is not working properly, ...
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1answer
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blocked.domain.gstatic.com - Where could this blocking be?

As of this morning we were having serious issues (partially loaded site with no functionality) accessing Google Drive which we use heavily. Other websites seemed to work fine. This is happening on ALL ...
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1answer
347 views

negative time for a ping echo reply

I was happily pinging in the net when suddenly: Pinging X with 32 bytes of data: Reply from .235: bytes=32 time=1444ms TTL=41 Reply from .235: bytes=32 time=1767ms TTL=41 Reply from .235: bytes=32 ...
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OSX nslookup can resolve a lan hostname, but ping cannot? [closed]

I'm having an issue which recurs every few days, whereby ping cannot resolve a hostname on my LAN (but nslookup is able to). This is on OSX 10.9.2 (latest). The machine in this case is called ...
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2answers
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openvpn: connection established, can't ping server tun interface (debian server, windows & os x clients)

My goal: I want to set up openVPN on a vServer from the company netcup, running Debian squeeze. I only want a VPN connection from client to server; clients should not be able to see each other, also ...
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9answers
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Why am I Unable to ping port 443 on Ubuntu?

I have opened port 443 through iptables: pkts bytes target prot opt in out source destination 45 2428 ACCEPT all -- lo * 0.0.0.0/0 0.0.0.0/0 6 1009 ACCEPT tcp -- * * 0.0.0.0/0 ...
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How network devices affect TTL

When I do a ping, I can see the TTL value for each packet. For every router that I insert in between my computer and the router that connects to the internet, the TTL value goes down by one. However, ...
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Ping hostname returns another hostname in output : what does it mean?

When I ping the server sip3.voip-centrex.net, I get this output: PING sip3.voip-centrex.net (194.98.81.144) 56(84) bytes of data. 64 bytes from mpfrrelay.michaelpage.fr (194.98.81.144): icmp_req=1 ...
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6answers
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Does a High Variation in Ping Response Times Indicate a Potential Network Issue?

My department has recently moved offices. The previous office was fine, but in the new office, the ping times from my PC to the 2 data centres usually varies a lot, like this: Reply from ...
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Why is DownOrNot and JustPing reporting that my website is down?

I was pinging my site with DownOrNot and it is reporting that my website is down from all locations. Then I pinged it with JustPing and it is reporting that my website is also down from all ...
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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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How does the ping command differentiate between its ICMP responses and anothers?

If I have two shells open each pinging the same host, how do the two shells differentiate between the ICMP responses coming back for each shell?
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IP address used by nslookup and ping is different

I have a web server hosted in the network. It has a domain name registered. However, I also host a DNS server for the LAN. So, when someone wants to access the web server, it would check the DNS ...
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1answer
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Can ping but cannot traceroute from Linux. Can do both from Windows. What gives?

So here's the issue. I have two different computers behind the same network. Both have the same gateway, IP address prefixes, etc. Computer 1: Windows XP IP 192.168.0.15 This computer can ping and ...
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3answers
530 views

Junior admin - how to discover/map the network to increase understanding?

I am a junior admin and have been tasked with gaining an understanding of the network. I know and use some of the servers on the network, so am able to tracert/ping them to see the names/addresses of ...
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Are network and broadcast IPs supposed to respond?

I have a /24 network that is subnetted into a bunch of small chunks. I have recently gone into each router on the network (mostly Cisco) in order to document how this network had been divided. Now ...
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How to Make sure Unstable/ Slow Connection is Due to ISP, Not Anything on My Side

I have a software, PingPlotter that allows me to identify the latency, round trip time, packet loss and a lot of other network statistics. I want to use those statistics as a proof that my ISP is ...
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4answers
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Ethernet Loopback plug - running a ping

For a project at work, I need to be able to test various Ethernet NICs by connecting them to a "loopback adapter plug", like this one on various embedded Linux boxen that come off a production ...
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1answer
269 views

How light is a ping?

Hopefully this question isn't too dumb. I'm wondering how expensive (system resource, and bandwidth wise) a ping is. If I have a small embedded linux device that has very limited ram, cpu, and ...
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How can I establish if a 566ms average response time is any good for my server?

One of my servers averages 566ms response time as measured by Pingdom ( pingdom.com ). Is this a good score? Should I be doing more to optimise it?
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How can I tell when a Mac switches access points?

I want to be able to tell when a MacBook (running OS 10.5) switches from one wireless access point to another. In the building I am in, with several wireless access points (all Airport Extremes, all ...
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1answer
372 views

How to ping ipv6 interface

I'm trying to get familiar with ipv6 I don't understand why I can't ping this interface at the inet6 addr eth1 Link encap:Ethernet HWaddr 08:00:27:77:9e:77 inet addr:192.168.33.10 ...
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ping https when ICMP is blocked

I working with web servers that ICMP is disabled on them. On the other hand they answer to some https requests. I'm basically looking for http like ping capabilities in order to check if another ...
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2answers
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Configure static IPv6 on Ubuntu

I'm trying to configure IPv6 on a dedicated Ubuntu server. My provider gave me a "/64" (whatever that is - I'm still confused) of IPv6 addresses. However, when I try to use them, I can't ping ...
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2answers
342 views

Odd results from ping

When I run this on an Ubuntu box: sudo ping google.com -c 25 -l 25 I get about 1 line back every 2 seconds despite the fact that it should (if I'm reading things correctly) send out all 25 packets ...
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2answers
257 views

NTP syncs with local timeserver but not NTP pool servers

I setup an NTP server on a machine in another subnet and tried to ync my machine with the server and it works well. But when I try to ust the pool.ntp.org servers (I tried 0.pool.ntp.org, ...
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3answers
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Domain Controller has mysterious 3rd IP Address

i have a domain controller with 2 NIC's. For some reason when i ping it from other computers, both on and off the domain it is responding from an ipaddress that doesnt belong to either of them. Does ...
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5answers
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Strange network connectivity problem

Here is my network connectivity: cable modem | |(WAN) wrt54g (default gateway, 192.168.1.1) -- earth |(LAN) | Simple Switch1 | | | | | SimpleSwitch2- ...
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1answer
506 views

Ping fails with the record route option

I'm having trouble with the record route (-R) option of the ping command in Linux. It appears that when I run the command without this option, I am able to receive a response from a range of servers ...
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2answers
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NetBIOS names over VPN

I have a Windows Server 2008 R2 box hosting a VPN to grant remote access to a home network. The network does not and will not have a domain. (I need FUS on XP machines) The VPN works fine, except ...
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3answers
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MTU problems? 'Request timed out'

I've been trying to figure out why some(very few) of the people who visit my site have random slowdowns and error pages('page cannot be loaded'). The random slowdowns and error pages never happen for ...
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1answer
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Why does an IPv6 route added before virtual machine is started not work

I have an external server at Hetzner with Debian 7 and trying to setup KVM with IPv6 Routing (the same setup works for IPv4 without problems). I have one Ubuntu Server VM with two interfaces which ...
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1answer
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OpenVPN and one way pings

Network configuration I have set up a network: Appropriate ports of computers in 192.168.87.0/24 are forwarded on TP-LINK router to be seen "all over the world". IP forwarding in enabled on ...
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1answer
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Wget works, Ping doesn't

There are some anomalies on a Virtuozzo virtualized Debian 4 (I know, I'm gonna upgrade this one asap, but there dependences). We run some Websites on this one. And a view Days ago exmi4 wasnt able to ...
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Why slow (500-4500ms) ping times to google.com over Wi-Fi?

I regularly get ping times (to google.com) on my netbook over wireless (802.11) of: 500-4500ms for about half the time 100-150ms for the rest of the time. It seems to switch back and forth on the ...