MTR: Advanced Network Diagnostics

MTR (My Traceroute) combines ping and traceroute in a single interactive tool. It's the standard for diagnosing network problems between two hosts: packet loss, high latency, asymmetric routing.

• router.deluxhost.net 0.0% 100 0.3 0.3 0.2 0.5 0.1
• 10.10.1.1 0.0% 100 1.2 1.1 0.9 2.1 0.2
• 185.1.2.3 0.0% 100 3.4 3.5 3.1 4.2 0.2
• ae1.cr1.fra1.example.net 0.0% 100 12.1 12.3 11.9 13.1 0.3
• ??? 100% 100 0.0 0.0 0.0 0.0 0.0
• 142.250.x.x 0.0% 100 22.4 22.6 22.1 24.0 0.4
• google.com 0.0% 100 23.1 23.2 22.8 24.5 0.4

Normal Packet Loss (Ignore It)

Many transit routers block ICMP (the protocol used by MTR) for security policy. If the next node shows 0% loss, there's no problem: the router simply doesn't respond to pings.

Always look at the node after the one with loss. If the next one is 0%, the loss on the previous node is artificial (ICMP rate limiting). If loss propagates to the destination, the problem is real.

Real Packet Loss

Loss starts at node 4 and propagates: the problem is on the link between node 3 and node 4. Report to your provider.

High Latency on a Single Node

Node 4 responds with 450ms but node 5 is back to 22ms: node 4 has only ICMP rate limiting, there's no real problem. The effective latency is that of the destination.

Real High Latency Problem

High latency propagates to the destination: real problem starting at node 4.

• ??? 100% 100 0.0 0.0 0.0 0.0 0.0
• ae1.cr1.fra1.example.net 15.0% 100 45.2 44.8 12.1 90.1 18.3
• 142.250.x.x 15.0% 100 46.1 45.0 12.3 91.0 18.1
• google.com 15.0% 100 46.5 45.2 12.5 92.0 18.4
• ae1.example.net 0.0% 100 450.2 448.1 440.0 460.0 4.2
• 142.250.x.x 0.0% 100 22.4 22.6 22.1 24.0 0.4
• ae1.example.net 0.0% 100 450.2 448.1 440.0 460.0 4.2
• 142.250.x.x 0.0% 100 460.1 459.3 449.0 470.0 4.1
• google.com 0.0% 100 461.5 460.2 450.0 471.0 4.3

Network problems are often asymmetric: outbound works but inbound doesn't (or vice versa). For complete diagnosis, you need two MTR runs: one from your PC to the server, and one from the server to your IP.

# From the server to your IP (example)
mtr --report --report-cycles 100 --no-dns YOUR_PUBLIC_IP

To find your public IP:

curl ifconfig.me

Diagnose to DeluxHost Gateway

# Replace with your VPS IP
mtr --report --report-cycles 50 --no-dns YOUR_VPS_IP

Verify Routing to a Specific Datacenter

# Check the path to an IP in a specific DC
mtr --report --tcp --port 80 --no-dns DESTINATION_IP

MTR with TCP Instead of ICMP

Useful if ICMP is blocked (e.g., to a web server):

mtr --tcp --port 443 google.com
mtr --tcp --port 80 tuodominio.com

Always attach MTR output when reporting:

Always provide both directions (from your PC to server AND from server to your PC) to allow complete diagnosis.

• High lag/latency on the server
• Packet loss during connections
• Intermittent disconnections
• Anomalous routing to certain regions