How to Troubleshoot “No Internet”
The fastest way to fix "no internet" is to test bottom-up through the layers: physical link → IP address → gateway → DNS → application. Each step has one command that either passes (move up) or fails (you found it).
Step 1 — physical & link
Is the cable/Wi-Fi connected? Check link lights and ipconfig / ip a. "Media disconnected" means a Layer 1 problem — fix the cable or Wi-Fi first.
Step 2 — do you have a valid IP?
ipconfig /all (Windows) ip addr (Linux)
A 169.254.x.x address (APIPA) means DHCP failed — you never got an address. Renew it: ipconfig /renew. No DHCP server, bad cable, or wrong VLAN are common causes.
Step 3 — can you reach the gateway?
ping <default gateway>
Fails → the problem is between you and your router (local). Passes → your local network is fine; move on.
Step 4 — is it internet or DNS?
ping 8.8.8.8 # reach the internet by IP ping google.com # reach it by name
If 8.8.8.8 works but google.com fails, it is a DNS problem, not connectivity. Check your DNS server or try nslookup google.com.
Step 5 — trace the path
tracert google.com (Windows) traceroute google.com (Linux)
The last responding hop shows how far traffic gets before it dies — inside your network, at the ISP, or beyond.
The quick checklist
- Link light / Wi-Fi connected?
- Valid IP (not 169.254.x.x)?
- Gateway pings?
- 8.8.8.8 pings? (connectivity)
- Name resolves? (DNS)
Whichever one first fails is your fault domain.
Frequently asked questions
What does a 169.254 IP address mean?
It is an APIPA address, assigned when a device cannot reach a DHCP server. It means DHCP failed — the device has no valid IP and cannot reach the network normally.
How do I know if it is a DNS problem?
If pinging 8.8.8.8 (an IP) works but pinging a name like google.com fails, connectivity is fine and DNS is the problem. Confirm with nslookup.
What is the first thing to check when there is no internet?
Start at Layer 1: is the cable or Wi-Fi actually connected and does the interface have a valid IP? Most "no internet" issues are a bad link or a failed DHCP address.
Why can I reach the gateway but not the internet?
Your local network works, so the fault is upstream — the router's WAN link, the ISP, or a routing/DNS issue beyond your gateway.
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