Ping/SSH not working 9.0.3, yes working 8.1.5

[brian-au]

Hi users,

I installed the latest stable 9.0.3, and the ICMP/ping response did not work (trying from another machine on same network). Pi V1B+, dhcp, 192.168.1.X
ssh did not work either, even though 'ps' shows sshd is running, and 'netstat' shows listening on port 22.

I installed the previous 8.1.5, ICMP/ping response worked out of the box and so did ssh.  I noticed that the 9.0.3 did not seem to build keys on first boot, while 8.1.5 did build keys.  EDIT: Ok, I have re-looked at this again, 9.0.3 does build keys, but it must do this 'silently', where on the 8.1.5 key building happens while you watch the bootup.

Is this behaviour expected for 9.0.3?  Sorry if I missed other posts on this topic, I did look for a while before posting this...

[brian-au]

ok, after seeing/finding the key build on 8.1.5 and realising that the keys should be saved, I ran the filetool.sh -b, and checked that it worked by looking at the date/time after a reboot, in
/usr/local/etc/ssh
ls -l

Did this same key-save on the 9.0.3, and after reboot the ssh and ping now works!

Because I'm seeking to setup this Pi as a headless server, I was looking to access via ssh straight out of the box on first boot, but looks like for some reason it didn't quite work on 9.0.3.

So in case this happens to others, this is the procedure:

setup microSD card
do first boot, with a screen and keyboard and network cable plugged in
after bootup to $ prompt, save the keys:$  filetool.sh -b
ifconfig (in case you need to find the dhcp IP address)
$ sudo reboot

Now enjoy ssh from elsewhere

Hope this helps someone else, and can anyone explain it?