This is my topology in my network.

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It's easy to know my server can communicate to

But when I traceroute the path, I only get one hop to it.

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My doubt is why it do not through

2 Answers 2


Based on your diagram, it looks like the "gateway switch" is one device (a router) with multiple IP addresses: and

Your server originates the first traceroute packet with a TTL of 1. The packet arrives at the "gateway switch" on the interface. The packet is accepted. The router notices that one of its own ip addresses ( is the destination and delivers the traceroute packet to the upper-layer stack for processing. This results in a response from

Going between and does not count as a "hop" because that is the same device.

The original traceroute packet never has its ttl decremented. Per When is an IPv4 TTL decremented and what is the drop condition? a router only decrements a ttl once it has decided to forward it.

More simply, your server IS ONE NETWORK HOP from Multiple interfaces/ips on a router is not a hop.


There is no hop for traceroute to see in between and since these are bound on the same device.

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