Can't SSH Into Headless Raspberry Pi 3 B+

Question

I have a Raspberry Pi 3 B+ and I'm trying to use it to run some servos. I'm brand new to the hardware and networking part of this setup - I only have experience with programming, but not this part.

I want to set up the Raspberry Pi so I can program on it using my laptop.

I'm using this guide. But I'm stuck on the part where I SSH into the Pi.

I flashed the recommended Raspian download + other software to an SD card and inserted it into the Pi. I saved the blank ssh file to the boot folder, as well as a wpa_supplicant.conf file that has this inside:

ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=US
network={
ssid="NETWORK SSID"
psk="YOUR PASSWORD"
key_mgmt=WPA-PSK
}

I found the IP of the Pi by plugging it into my router and using the Fing app to see the IP was 10.10.10.110. When I try to SSH into that address using Putty, it gives me a network error and says the connection timed out.

I try to ping the Pi from my laptop and it says destination host unreachable.

Any ideas?

Answer 1

You should verify that the IP ADDR 10.10.10.110 is your RPi Ethernet port. From your PC/Mac/Linux/whatever:

ping 10.10.10.110   
arp -a | grep --ignore-case b8:27:eb

EDIT: RPi 4 has a new OUI, and so the arp command must be modified as follows: 

arp -a |grep -E --ignore-case 'b8:27:eb|dc:a6:32' 

You should get something that looks like this:

? (10.10.10.110) at b8:27:eb:.... on en0 ifscope [ethernet] 

EDIT: Or like this if you have a RPi 4:

? (10.10.10.110) at dc:a6:32:.... on en0 ifscope [ethernet]

If you don't get a response like one of these, the device at IP address 10.10.10.110 is NOT a Raspberry Pi.

Q: How does this work?

A: Note that the first three octets of the MAC address are a.k.a. the OUI. The MAC address is a unique identifier for Ethernet hardware, and the OUI occupies the first three octets of the MAC address. Prior to the release of Raspberry Pi 4, all RPi's used the OUI b8:27:eb. Beginning with Raspberry pi 4, a different organization is responsible for production, and the new OUI is: dc:a6:32. The OUI then, tells us that one of the Raspberry Pi organizations has made the hardware, and so it must be (at least for now) a Raspberry Pi device!

And so, to address your situation: If the MAC address of the device at IP address 10.10.10.110 is not one of these two values, then it is not a Raspberry Pi.

Finding the IP address of your RPi is sort of tedious, but here's one straightforward way to do it. OTOH, if your network supports zero configuration networking (e.g. avahi), you may find your device by sshing to raspberrypi.local; e.g. ssh pi@raspberrypi.local.

Answer 2

I would confirm a few things first, before assuming it’s all wrong.

• is the empty ssh file inside the main sd card folder? Also known as the root folder.
• remember that when you boot once, the ssh file disappears unless you enable ssh through raspi-config
• is the IP really the one you say it is?
• do you have a cat5e or cat6 cable and an available port on your router?

The first two are self-explanatory, however, in order to find and configure the pi for headless boot, I would strongly recommend connecting to the network the old fashioned way first. Connecting an ethernet cable, it ensures it connects to the local network without a hitch and provides it with an IP faster and more reliably.

I do this every time I set up a Pi. Connect to ethernet, place the file and boot. I also use fing to find the IP addresses but I would recommend to run it before you plug it in, make note of the IP's present then boot the PI and run fing again, the different IP should he obvious and then try to ssh.

From there run sudo raspi-config FIRST! And enable ssh. Otherwise, you're going to have to keep adding the ssh file through the sd card.

Finally, you can add the wifi settings by modifying the wpa_supplicant using nano or vim.

Hope this helps you debug your issues with your Pi