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After configuring a new Raspberry Pi Zero W, I have not been able to ssh into it over WiFi. The IP address is assigned and pingable, but I get 'connection refused' errors.

After some research, I discovered one possible solution is to replace the SSH host keys on the pi.

But it's a Catch-22, because I can't login to the pi to change the keys that I need to change to be able to log into the pi.

What can I do?

Why do I need to replace host keys?

Short answer: I don't know. I don't even know if that's the only or best solution or just one workaround. Currently I'm wondering about a few things: The implications of installing Raspian full on headless Pis, also whether or not openssh got configured. One thing I did on both Pi's was added a dt overlay line in config.txt to enable ethernet over USB. Could have thwarted the boot/initialization sequence? Will run some experiments and post info if I learn anything new.

Configuration details: The way I configured my Pi's are as follows: Using Etcher.app on macOS, I flashed an SSD card with the full desktop version of Raspian, 2018-11-13-raspbian-stretch-full.img, downloaded from the Raspian site, and installed it on a Pi Zero W and a Pi 3B+, both headless, and used the headless approach to configuring WiFi and ssh (i.e. touched ssh in /boot and created wpa_supplicant.conf in /boot).

I didn't have this problem when I similarly installed Raspian lite (on my Pi 3B, about a month ago, 2018-10-09-raspbian-stretch-lite.img

Follow-up to @Milliway's comment below: This is the Reddit thread containing post that gave me the idea that regenerating host keys might fix the problem:

https://www.reddit.com/r/raspberry_pi/comments/704v5y/ssh_connection_refused_off_a_headless_setup/

After configuring a new Raspberry Pi Zero W, I have not been able to ssh into it over WiFi. The IP address is assigned and pingable, but I get 'connection refused' errors.

After some research, I discovered one possible solution is to replace the SSH host keys on the pi.

But it's a Catch-22, because I can't login to the pi to change the keys that I need to change to be able to log into the pi.

What can I do?

Why do I need to replace host keys?

Short answer: I don't know. I don't even know if that's the only or best solution or just one workaround. Host Keys are configured when ssh is configured. Did that configuration not run, or did it fail for some reason? One thing I did on both Pi's was added a dtoverlay=dwc2 line in config.txt to enable ethernet over USB. Could that have thwarted the boot/initialization sequence? Will run some experiments and post info if I learn anything new.

Configuration details: The way I configured my Pi's are as follows: Using Etcher.app on macOS, I flashed an SSD card with the full desktop version of Raspian, 2018-11-13-raspbian-stretch-full.img, downloaded from the Raspian site, and installed it on a Pi Zero W and a Pi 3B+, both headless, and used the headless approach to configuring WiFi and ssh (i.e. touched ssh in /boot and created wpa_supplicant.conf in /boot).

I didn't have this problem when I similarly installed Raspian lite (on my Pi 3B, about a month ago, 2018-10-09-raspbian-stretch-lite.img

Follow-up to @Milliway's comment below: This is the Reddit thread containing post that gave me the idea that regenerating host keys might fix the problem:

https://www.reddit.com/r/raspberry_pi/comments/704v5y/ssh_connection_refused_off_a_headless_setup/

After configuring a new headless Raspberry Pi Zero W and headless Raspberry Pi 3B+ with the full version of Raspian, I have not been able to ssh into it over WiFi. The IP address is assigned and pingable, but I get 'connection refused' errors when tryin to ssh into them.

After some research, I discovered one possible solution is to replace the SSH host keys on the pi.

But it's a Catch-22, because I can't login to the pi to change the keys that I need to change to be able to log into the pi.

What can I do?

Background detail: The way I configured my Pi's are as follows: Using Etcher.app on macOS, I flashed an SSD card with the full desktop version of Raspian, 2018-11-13-raspbian-stretch-full.img, downloaded from the Raspian site, and installed it on a Pi Zero W and a Pi 3B+, both headless, and used the headless approach to configuring WiFi and ssh (i.e. touched ssh in /boot and created wpa_supplicant.conf in /boot).

I didn't have this problem when I similarly installed Raspian lite (on my Pi 3B, about a month ago, 2018-10-09-raspbian-stretch-lite.img

At the moment I'm wondering if possibly installing the full Raspian on a headless Pi may thwart OpenSSH configuration (e.g. requires raspi-config to be run by user or something).

I will update this question if I find out the root cause to this, and whether the workaround is the best answer

Follow-up to @Milliway's comment below: This is the Reddit thread containing post that gave me the idea that regenerating host keys might fix the problem:

https://www.reddit.com/r/raspberry_pi/comments/704v5y/ssh_connection_refused_off_a_headless_setup/

After configuring a new Raspberry Pi Zero W, I have not been able to ssh into it over WiFi. The IP address is assigned and pingable, but I get 'connection refused' errors.

After some research, I discovered one possible solution is to replace the SSH host keys on the pi.

But it's a Catch-22, because I can't login to the pi to change the keys that I need to change to be able to log into the pi.

What can I do?

Why do I need to replace host keys?

Short answer: I don't know. I don't even know if that's the only or best solution or just one workaround. Currently I'm wondering about a few things: The implications of installing Raspian full on headless Pis, also whether or not openssh got configured. One thing I did on both Pi's was added a dt overlay line in config.txt to enable ethernet over USB. Could have thwarted the boot/initialization sequence? Will run some experiments and post info if I learn anything new.

Configuration details: The way I configured my Pi's are as follows: Using Etcher.app on macOS, I flashed an SSD card with the full desktop version of Raspian, 2018-11-13-raspbian-stretch-full.img, downloaded from the Raspian site, and installed it on a Pi Zero W and a Pi 3B+, both headless, and used the headless approach to configuring WiFi and ssh (i.e. touched ssh in /boot and created wpa_supplicant.conf in /boot).

I didn't have this problem when I similarly installed Raspian lite (on my Pi 3B, about a month ago, 2018-10-09-raspbian-stretch-lite.img

Follow-up to @Milliway's comment below: This is the Reddit thread containing post that gave me the idea that regenerating host keys might fix the problem:

https://www.reddit.com/r/raspberry_pi/comments/704v5y/ssh_connection_refused_off_a_headless_setup/

After configuring a new Raspberry Pi Zero W, I have not been able to ssh into it over WiFi. The IP address is assigned and pingable, but I get 'connection refused' errors.

After some research, I discovered one possible solution is to replace the SSH host keys on the pi.

But it's a Catch-22, because I can't login to the pi to change the keys that I need to change to be able to log into the pi.

What can I do?

Background detail: The way I configured my Pi's are as follows: Using Etcher.app on macOS, I flashed an SSD card with the full desktop version of Raspian, 2018-11-13-raspbian-stretch-full.img, downloaded from the Raspian site, and installed it on a Pi Zero W and a Pi 3B+, both headless, and used the headless approach to configuring WiFi and ssh (i.e. touched ssh in /boot and created wpa_supplicant.conf in /boot).

I didn't have this problem when I similarly installed Raspian lite (on my Pi 3B, about a month ago, 2018-10-09-raspbian-stretch-lite.img

At the moment I'm wondering if possibly installing the full Raspian on a headless Pi may thwart OpenSSH configuration (e.g. requires raspi-config to be run by user or something).

I will update this question if I find out the root cause to this, and whether the workaround is the best answer

Follow-up to @Milliway's comment below: This is the Reddit thread containing post that gave me the idea that regenerating host keys might fix the problem:

https://www.reddit.com/r/raspberry_pi/comments/704v5y/ssh_connection_refused_off_a_headless_setup/

After configuring a new headless Raspberry Pi Zero W and headless Raspberry Pi 3B+ with the full version of Raspian, I have not been able to ssh into it over WiFi. The IP address is assigned and pingable, but I get 'connection refused' errors when tryin to ssh into them.

After some research, I discovered one possible solution is to replace the SSH host keys on the pi.

But it's a Catch-22, because I can't login to the pi to change the keys that I need to change to be able to log into the pi.

What can I do?

Background detail: The way I configured my Pi's are as follows: Using Etcher.app on macOS, I flashed an SSD card with the full desktop version of Raspian, 2018-11-13-raspbian-stretch-full.img, downloaded from the Raspian site, and installed it on a Pi Zero W and a Pi 3B+, both headless, and used the headless approach to configuring WiFi and ssh (i.e. touched ssh in /boot and created wpa_supplicant.conf in /boot).

I didn't have this problem when I similarly installed Raspian lite (on my Pi 3B, about a month ago, 2018-10-09-raspbian-stretch-lite.img

At the moment I'm wondering if possibly installing the full Raspian on a headless Pi may thwart OpenSSH configuration (e.g. requires raspi-config to be run by user or something).

I will update this question if I find out the root cause to this, and whether the workaround is the best answer

Follow-up to @Milliway's comment below: This is the Reddit thread containing post that gave me the idea that regenerating host keys might fix the problem:

https://www.reddit.com/r/raspberry_pi/comments/704v5y/ssh_connection_refused_off_a_headless_setup/