Traceroute

Traceroute shows the path packets take from the site's server in the Moscow region to the domain or IP address you enter. If you enter a domain, the tool uses its first IPv4 address. Each hop receives three ICMP probes, and the path is limited to 20 hops. For every hop that responded, the table shows its address, reverse name, network number, operator, and country. The first rows belong to the hosting provider's internal network, and those hops have no name or operator. The path from your own ISP to the same site will be different: other operators, a different number of hops, and usually only the tail, the site's own network, stays the same.

Why some hops show asterisks instead of a reply

Asterisks mean the hop did not answer the probe. Transit still works, because the hops further down the table do answer. The reason is a network setting, and backbone operators and sites themselves are most often configured this way. Ignore the asterisks entirely as long as at least one row below contains numbers. The route is alive. In a trace to 77.88.8.8, hops 6–8 stayed silent while hop 9, the destination itself, replied in 3 ms.

How to read the time at a hop

The time in a row is the round trip of a probe to that hop, not to the destination. Equipment answers probes outside its main traffic flow, so the number says nothing about how fast packets pass through the hop. In one trace, hop 2 showed 115 ms while the hop right after it, hop 3, showed 0.6 ms. Jumps like these do not mean the network is fast in one place and slow in another. Judge the delay to the site by the last hop, the destination. If one hop shows different addresses across its three probes, load balancing is sending the probes along different paths.

The trace stops short: what to do next

A silent last hop does not mean the site is down: ICMP replies are filtered at the network border and on the server itself. The verdict names the last hop that answered. That is the point beyond which the probes did not pass. If the report says the host is unreachable, the network is unreachable, or communication is blocked by rules, the refusal came from a specific piece of equipment.

Before drawing conclusions, ping the host: it will show whether the host answers and how many packets are lost. If the losses are confirmed, take the complaint to the operator of the last hop. The table's network and operator column gives a hint whose network it is, and an IP to ASN lookup will tell you for sure.