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27

The website runs on a server process. When you shut down the server process, the server does not magically turn off. Also not when you misconfigure your firewall (and block port 80) neither does the server go off nor does the ICMP rule in the firewall get deleted.


14

If I'm not mistaken, the problem is that your registrar has published DS records for your domain - that is, DNSSEC signing keys: [me@risby player]$ dig ds ultreyatours.com [...] ;; ANSWER SECTION: ultreyatours.com. 85920 IN DS 49864 8 1 0152C1213569799FAFA42C7699A20132A293F908 ultreyatours.com. 85920 IN DS 20536 8 1 ...


10

Traceroute uses ICMP protocol to reach an address, and a HTTP server use HTTP protocol, different ports, and different approaches. I can reach an address via ICMP echo request but, if the port I'm trying to communicate is closed or freezed somehow, I'll get a timeout error. And if you're sure the server is up and the port is up (listening), is better to ...


9

You're leaving out a crucial piece of information, which is the subnet mask. You're making an incorrect assumption that these two hosts are in the same network/subnet based solely on the octet values without considering the subnet mask that each host is using. They could very well be in different networks. Think of a house address. If I told you that I ...


8

The same company host doesn't means that they are on the same network architecture... so route and ping might be different if they are connected to different network elements (proxy, firewall, loadbalancers...). As they are on different subnetworks, they also might be in different Datacenters which means different physical location, so the ping time might be ...


5

This does not look Powershell-related at all. Instead, it looks like your network (after 192.168.160.2) is filtering at least the ICMP Time exceeded responses, which is what tracert / traceroute relies upon to generate the routing path trace. It does not matter what traceroute implementation you are using or how you tweak the parameters of the call - your ...


5

What Is a Virtual-Host? Some web-servers, like Apache, can be configured to use what's called virtual-hosting; essentially a local redirection service. In essence, it works like this: the web server(we're going to assume it's Apache2 in this case) will choose what documents to serve depending on what domain and/or IP address the request was from. For ...


5

Setting an upper limit for packet size was done for two reasons: ensure reliable transmission of the data (longer data are more susceptible to being corrupted and their CRC have lower changes of detecting/correcting the corruption); ensure that all Ethernet-compliant device have at least a 1500 byte buffer to send/receive packets. As you suggested, the ...


5

Shorter answer: Thanks for providing the actual IP addresses. This helps us see what you are seeing to an extent. And here is what I am seeing. 37.211.166.178 appears to be unreachable while 37.211.15.247 is fine. So the difference in ping times you initially saw could be due to an outage on that hosting provider’s network associated with that address. It ...


5

If you are getting different traceroute results, it is because the routing is being handled differently. This could be because the hosts are not on the same network (as Paul's first comment under your question noted... I am agreeing with his comment... many companies these days are international, so being part of the same company doesn't necessarily mean ...


3

It means that a packet with a tweaked TTL did not return an appropriate ICMP TTL exceeded packet, or that those packets were lost on the way back, within the given period traceroute waits for them. This CAN mean, that the host on the way is not generating them properly if at all. There is little you can do about this. You can change the protocol traceroute ...


3

No. Traceroute relies on ICMP Time Exceeded packets.


3

An ISP that do network attribution change nothing, as each modem cable and such gear report to the ISP server upstream. Having a static IP just mean your router is not configured to ask an IP from a DHCP server from the ISP, but the packet, or the route use the same physical line to get to the ISP gear to reach the internet backbone. A good example is ISP ...


2

This question has been addressed by Ladadadada here : Does traceroute use UDP or ICMP or both? The type of packet that is sent differs depending on the implementation. By default Windows tracert uses ICMP and both Mac OS X and Linux traceroute use UDP. I don't have BSD or Solaris machines or any other OS on hand to check but the man page for the Mac OS X ...


2

Most probably the pong from ping is blocked/gets discarded, while traceroute uses an error message form a node/hop to determine the route. Traceroute is not a standard tool, in that it uses a trick to get the information. The trick is to manipulate the TTL, so the hop responds with an ICMP error (ICMP TTL exceeded), and that is why this is possible.


1

Found this googling a bit: Ethernet frame has 8 byte preamble, 6 byte source and 6 byte destination mac address, mac type of 2 bytes, and 4 bytes CRC. Assuming the MTU payload to be 1500 the total number of bytes comes to 1500 + 8 + 6 + 6 + 2 + 4 = 1526 bytes. Now between each frame there is a inter frame gap of 12 bytes which constitues 9.6micro ...


1

The number of lines in the trace output will indicate how many times the hop limit (also called time to live) has been decreased on the path from you towards your peer. Thus a device which does not decrease the hop limit, will be invisible to the trace. For example switches will not be seen in the trace, because they operate at a lower layer than IP. What ...


1

!A means administratively prohibited. It's a slightly friendly way of telling you you're "not allowed" than just dropping traffic. (And is usually because a firewall is configure to deny this traffic for some reason).


1

Traceroute is working fine. These aren't domains, so there is nothing to resolve. What you see are the IPv6 addresses of the hops (thatis, the routers between you and the target). When you use the -4 option, traceroute traces the route from your machine to the destination using IPv4 addresses only instead. Note that the IPv4 traceroute path and the IPv6 ...


1

It means that the affected host (in your example, the second one) did not reply to the traceroute. As by default traceroute uses an UDP port, you can change the discovery protocol to use ICMP/PING using the "-I" option. Apart that, you can not do anything more.


1

GeoIP lookups do not necessarily reflect the physical location of the IP address. GeoIP lookups rely soley on the whois information of the netblock. The whois information is often just set to the corporate headquarters of the netblock owner. The most accurate indicator you have of the physical location of an IP address comes from the hostnames of the hops ...


1

In the internet different pieces of WAN are connected together, but their connection path isn't constant. Links come up and down, network outages occur, network load changes - this results in the dynamis protocol changes, which ISP interexchange. And this is the most possible reason of the icmp latency changes. Using two traceroute outputs - one taken while ...


1

The only thing a trace route indicates is how long an ICMP packet takes to get to and from each route hop between your source and destination IPs. Period. If you want to test how a certain application will perform, you need to test and profile that application.


1

Because ISPs choose the most cheapest paths for them. If routing traffic to the ISP (C) for ISP (A) is cheaper through ISP (D) (which is probably a big company with really big links, which sells the traffic in significant volumes and because of that have lower prices) than by ISP (B) (which can be a pretty small ISP with small resources, so they traffic ...


1

Whether your IP is assigned via DHCP or static it should not effect how ping operates. Once the IP is assigned ICMP does not care how you got it.


1

Hi I'm late but in the event you're still curious... The quote from R Steenbergen's NANOG slide is correct. The behaviour is defined in Section 4.3.2.4 of RFC1812, which states: the IP source address in an ICMP message originated by the router MUST be one of the IP addresses associated with the physical interface over which the ICMP message is ...



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