Questions tagged [traceroute]
The traceroute tag has no usage guidance.
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traceroute on server works for one website but not another
On a server, I used traceroute to both bing.com and baidu.com. The dns server is set to 8.8.8.8. It works for bing.com but not baidu.com.
What might be the cause for the issue? (I suspect this might ...
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Does traceroute/MTR results in the same overall latency from src and dest direction and vice versa?
I was quite convinced that traceroute/MTR from A to B and B to A will have the same overall latency at the last hop as the reply would have been returning from the reverse direction, meaning i if take ...
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iptables - Cannot traceroute from container behind NAT if SMTP port forwarding set in host
I've created a fairly simple port forwarding rule to redirect requests to port 25 to a specific container in the virtual environment:
iptables -t nat -A PREROUTING -p tcp --dport 25 -j DNAT --to 10.10....
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traceroute for HTTP
I'm trying to track down an elusive issue where a particular URL refuses to work. My investigations so far suggests there's some kind of DPI firewall/proxy/whatever between the client and server that ...
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traceroute shows stars but netcat reaches the port
I have several (virtual) machines with Centos 7 in the same subnet with several instances of my app running on each of them. I need to test how the apps can reach each other by UDP.
I'm trying to ...
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VPS can not be reached in any way from some clients; IP routing issue?
I have been running a VPS which is situated in Amsterdam. It has not given any problems, and can be reached from most locations reliably.
Except when a French customer was not able to reach the server ...
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The packet goes through the other router
I want to connect two hosts in parallel with two different models of virtual routers.
These are made redundant by VRRP.
Originally, packets are sent through only one of the routers.
However, when the ...
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Different traceroute response times for same path
When troubleshooting for slow Internet speed on one computer, I am having systematic slower response times between two computers when running tacert, for any domain.They are both connected to the same ...
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traceroute: sometimes routers don't respond and user sees timeouts
I'm an admin of small network and I'm investigating a problem my users complain about. The root of their complaints is traceroute: sometimes routers along the path simply don't respond to traceroute ...
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Traceroute - Header Link CURL result Issue
We have systematic CURLs run every 15 mins - 2 hours from this system and logging their status. Every other CURL for the past 2 months has succeeded except this. Is there a way to identify why this ...
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Traceroute works but nc fails - Where is my port being blocked?
I am trying to troubleshoot two Azure VNETs that have been peered together. Lets call these VNETs A and B. There are multiple services running on a VM in VNET A on different ports. I am trying to ...
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Does traceroute use the same path?
I was a little bit confused about the use of traceroute.
According to this
The traceroute command is used to see how packets are getting routed. It works by sending packets with increasing TTL values,...
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130
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Subdomain with variable IP
Subdomains like http://3qax.munzer.webproxy.idc-lorien-apiver01-repay-action.bh-arppofind.comssets.mealcardhss-int-bh-awwwppofind.wire.2.homeetingroom.walmartmobile.cn presents a behavior that when I ...
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Why traceroute with different arguments makes different routes?
I was studying how traceroute works and now im feeling kinda stuck.
sudo traceroute -T aws.com
traceroute to aws.com (13.227.211.129), 30 hops max, 60 byte packets
1 * * *
2 100.64.0.103 (100.64.0....
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What is this private LAN address accessible through my ISP?
Recently some websites I regularly visit (most recently docker.com, atlasobscura.com; both of these sites return an issue with a fortinet-ca2 certificate) have started showing certificate issues on my ...
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Ping and tracert misbehaving on my device only
I'm posting this here instead of the networking forum because the issue is isolated on my PC
Long story short:
Pinging anything always results in a successful reply from my private IP
Any traceroute ...
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when router sends ICMP protocol error message how does it set it's own TTL?
when using (traceroute -q 1 serverAddress), we know that it starts with TTL(Time to Live) = 1.
when it goes through router, the router decrements TTL by 1. If TTL becomes 0 at that router, it sends ...
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opened port for tcp/udp using iptables for traceroute, but it still fails, why?
Traceroute to the server fails, this is description of the problem:
root@newTralev ~ # ifconfig
eth0 Link encap:Ethernet HWaddr 74:d0:2b:9a:85:74
inet addr:176.9.18.37 Bcast:176.9....
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Can Traceroute detect a load balancer?
Can traceroute detect a load balancer sitting between an application server and a database?
After running a traceroute from application server to database I only received one hop. The hop was the ...
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Why does RCN route addresses in 10.0.0.0/8 to some public machine?
I have a colleague who uses RCN (no idea if that's relevant). When he runs traceroute on a private IP address like 10.22.32.136, it seems to get routed to some "public" machine. For example, ...
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How to interpret asterisks in a tracert command. Does this sugest an issue?
we have a 3rd party application installed on our application server, "myservername." The 3rd part company tells us that the application is very chatty and quickly performs poorly unless ...
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Two or more hosts in traceroute answer
Hi I have strange behavior of a traceroute to one of my public IP's
In one of a line I have multiple hostnames with timing
like in the folowing example, on the 5th line
traceroute to dns.abc.com (111....
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Why would traceroute print destination ip for each hop instead of router ip?
$ traceroute -n 8.8.8.8
traceroute to 8.8.8.8 (8.8.8.8), 30 hops max, 60 byte packets
1 8.8.8.8 3.158 ms 4.246 ms 5.054 ms
2 * * *
3 8.8.8.8 9.121 ms 10.245 ms 9.327 ms
4 8.8.8.8 12.134 ...
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What is blocking my mysql connection?
We run several docker images on a VM.
sudo iptables -S shows a lot of docker networking.
We try to connect to an external MySQL database in another net.
mysql --host=mysql.example.org --user=thisuser ...
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How to trace UDP blocking for DNS port 53
Recently both of our DNS servers stopped responding to incoming UDP on port 53, tested with dig and it works with TCP. They both have common ISP. Is there any way to traverse route and find out ...
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What may cause a request being sent with a TTL of 64 to fail on connection to a destination ip that traceroute shows is 33 hops away?
From within a docker container (running ubuntu 18) running on AWS ECS I'm attempting to establish a connection to an outside data center. We've troubleshot the issue to where we believe it's the ...
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Why the packet loss of ping and traceroute is different
I have an IP address on 12th hop. When I send an icmp request packet with TTL 11 to this IP, the packet loss at the 11th hop is 0%.
However, if I ping the IP address of the 11th hop, or use TTL 11 to ...
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Strange traceroute behavior when using iptables/nat to redirect an IP
At a client of mine, who has a LAN of 10.0.1.0/24, they have a Windows machine with ip 10.0.1.8 that hosts a rather old legacy application (that of course no one has the source code for) that wants to ...
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Traceroute vs tracert
I'm having the following issue:
Running tracert from Windows 7 returns all the hops to a given server.
Running traceroute from Fedora 30, using the same connection and the same destination, ...
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Why this ip range is only showing * * *?
I've got a question.
When I try to do this on GNU/Linux:
traceroute -m 255 -I [the_ip]
Then I get this:
192.0.0.1 (192.0.0.1) 6.788 ms 6.774 ms 6.781 ms
62.214.36.201 (62.214.36.201) 7.672 ms ...
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How is the number of routers between source and destination known beforehand?
I was studying Computer Networking book of Kurose and Ross and under Traceroute subsection I've read following:
More specifically, suppose there are N - 1 routers between the source and the
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First traceroute hop always slow. Why?
Browsers in my LAN, no matter the device, are always slow to connect to internet servers, but after the connection is made webpages download rather fast.
Speedtest.net reports what I would call a ...
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Why is my data throughput only 1G of possible 10G if I setup an ethernet bridge?
My setup is a Windows 10 PC with 10G card (LR-LINK 6880BT) and a Synology DS1618+ NAS with 10G card (Synology E10G18-T1). Both 10G ports are connected directly to avoid buying a 10G switch.
A) How ...
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Adding a hop using `ip route add` makes traceroute stop at the first hop
I am practising for LFCS. I have two virtual machines, ubuntu 18.04 both.
On machine1, when i run traceroute 8.8.8.8 I have a normal output. When on machine1 I run
sudo ip route add 8.8.0.0/16 ...
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Traceroute to check NTP - possible?
In the past I mostly used tcptraceroute to check http and ssh.
Now I need to check if my host can reach the NTP server.
Is this possible at all?
I have two machines.
At application level I see: ...
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Latency jumps in first, middle and last mile of path
I work for SD-WAN company providing an all in one solution edge router(Like FORTINET but not FORTINET).
We have one customer in particular that has such a hard time with our services i.e. gift card ...
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TTL Changes During Continuous Ping
We use Viasat and have the modem plugged directly into a linux based load balancer.
I SSH'ed into the loadbalancer using putty and pinged google
When I pinged google this is the result:
- PING 8.8....
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How do I do traceroute/tracepath without any admin privileges?
Basically, I need to "trace a packet from my computer to the host" to diagnose a network issue and I do not need any fancy additional functionality.
Redirect me to the right place if this is not the ...
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Tracert high latency [duplicate]
I have used tracert command to check local network status, at the second hop I get random- high numbers for latency,(attached file), but when I use ping the total latency has an average of 1ms.
What ...
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Layer 3 Device ICMP behavior and impact on tracert
Is it possible to configure a layer 3 device to set the TTL of all ICMP echo request packets to zero and not send out ICMP Time Exceeded message ? If so, wouldn't this make it impossible for tracert ...
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Connection timout between two IP troubleshooting
I have a client with a webserver and a VPS server with a webserver and a mailserver. These machines have to exchange data via REST API but I have a problem, they are not reachable each other over HTTP ...
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Tracert doesn't return to prompt after "trace complete"?
I am trying to run some tracert via cmd in Windows, but both manually and via a batch script the trace doesn't progress after "trace complete".
In the script it won't move to the next trace and ...
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tcptraceroute: Hop does not reply
AFAIK tcptraceroute is the best tool to check if a firewall is blocking the tcp connection to a service. (If you know a better tool, please let leave a comment)
Some hops do not reply. See * * *
...
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Why does traceroute ended with additional hop after the destination?
If nothing block the traffic, traceroute normally ends with the destination IP as the last hop. (10.1.1.10 in this case)
Normal traceroute would be like this.
user@linux:~$ traceroute 10.1.1.10
...
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website hosted in aws ec2 is not loading
I have a website hosted in aws ec2 which stopped loading since few days onwards no clue whatsoever, below the output of traceroute please help
Tracing route to 126news.com [18.221.68.117]
over a ...
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Add hop in tracert
Basically, I'm interested how to make one of my servers hop in tracert.
My first server is located within DC in France
My second server if located within DC in Russia
I want my 1st server to be in ...
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Some IP addresses are unreachable due to invalid route
I want to connect to remote machines. The problem is that I can connect to every machine except one. After some invertigation I found that problem is in route. Here is example:
PS C:\Users\Alex> ...
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Traceroute not returning result whereas ssh is working fine
Maybe it's a dumb question, so please bear with me as I am novice to networking. While trying to debug a connection problem to a server today I observed the following two things -
I am able to ssh (...
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Why does traceroute -T add hops and intermediary asterisks?
Behold, traceroute without any options:
$ traceroute google.com
traceroute to google.com (172.217.4.142), 30 hops max, 60 byte packets
1 10.14.62.1 (10.14.62.1) 0.619 ms 0.685 ms 0.806 ms
2 10....
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telnet: Unable to connect to remote host: Connection timed out
Setting up a postfix server, trying to figure out why it's not working. Here's a command that I ran while troubleshooting. I expected to be able to connect, but could not.
lol@foldingmachine:~$ ...
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