[EdLUG] SSH - ssh-copy-id problem | RPi | Ubuntu.

Tue Mar 30 20:58:47 UTC 2021

Time for a left-field idea. This is PiOS right? Raspberry pi OS?

When I log in with the default user (pi) using any method, and still have
the default password set on that account, it triggers a message on the
console telling me to change the password.

Now, that surely should only come up in an interactive shell, it doesn't
ask for any input either, but I think it is specific to PiOS, so ... maybe
it's badly implemented somehow.

Question: do you still have the default password set, and does this problem
still happen if you've changed it?

(Told you it was a bit off-the-wall!)

AK

On Tue, 30 Mar 2021 at 21:48, Gordon Gray <gordo.gray at gmail.com> wrote:

> Hi all. I’m enjoying this thread. My approach to problem solve would be
> the one Tai described: run the commands from the script manually.
>
> One thing I noticed though is this line in the debug output
>
> debug1: Sending env LANG = en_GB.UTF-8
>
> I suspect you might need to edit your locale as described here:
>
>
> https://unix.stackexchange.com/questions/347914/how-to-set-lc-all-en-gb-utf-8-in-raspbian
>
> Cheers,
> Gordon
>
>
> On Tue, 30 Mar 2021 at 21:39, <tengo at tutanota.de> wrote:
>
>> Hi Nick,
>>
>> Both are 1500.
>>
>> Regards,
>>
>> John
>>
>> -----------
>>
>>
>>
>> 30 Mar 2021, 21:22 by nick at dischord.org:
>>
>> Can you check network interface MTU settings?  A simple 'ip li' should do
>> the trick.  Make sure they're all the same;  1500 being the default for
>> Ethernet, or if you've enabled jumbo frames then perhaps 9000.  The key
>> thing is that they're all exactly the same.
>>
>> --
>>
>> -Nick
>>
>>
>> On Tue, 30 Mar 2021 at 21:08, <tengo at tutanota.de> wrote:
>>
>> Thanks for all the replies.
>>
>> Quiet a lot of discussion and suggestions and things I don't quite
>> understand.  I'm willing to try more troubleshooting, but for now here's a
>> copy of the output from ssh-copy-id with DEBUG3 -
>> https://file.re/2021/03/30/ssh-copy-id-debug3/ . It will be available
>> for 24 hours.
>>
>> @Tai - Thanks for your suggestion. I'm not looking for a work around as I
>> think this issue is also stopping me from using Ansible to manage the Pi.
>>
>> For example, if I manually copy the key to the Pi I can SSH without any
>> issues. However, if I run a simple Ansible ad-hoc command using the "ping"
>> module it hangs too. This module makes its connection with SSH and I'm
>> using the same account (pi). I also encountered issues when I tried the ssh
>> extension in VS code too. Not too bothered about VS code extension (in
>> preview), but it's also using ssh and failing.
>>
>> None of this is a problem from my other laptop.
>>
>> -----------
>>
>>
>>
>> 30 Mar 2021, 16:48 by dch.tai at gmail.com:
>>
>> Back on track :-)
>>
>> You could try running as Geetam suggested
>>
>>     ssh-copy-id -o LogLevel=DEBUG3 pi@$IP
>>
>> for even more verbose output (equivalent to running ssh -vvv ...)
>>
>>
>> If you "just want it to work", and regular SSH seems to work, you could
>> instead run this:
>>
>>     akeysfile=".ssh/authorized_keys"
>>     ssh pi@"$IP" "cd ; umask 077 ; mkdir -p .ssh && touch $akeysfile &&
>> cat >> $akeysfile" < "$HOME/.ssh/id_rsa.pub"
>>
>> This is the simplified version of what ssh-copy-id tries to do, except
>> the latter does extra checking of various things. This one just bluntly and
>> forcibly append your existing public id content to the remote auth keys
>> file. Manually adding a key is what I do to grant access to other people
>> onto boxes, this technique is fine.
>>
>>
>> From reading the ssh-copy-id script, I can see it does some complex
>> jiggery-pokery with trying to read the public key file and determine if
>> it's the latest, if it's already over on the other side, etc. That it
>> prompts means there's a connection. That it hangs on that command, makes it
>> sound like the printf isn't doing what is expected and the `cat` being run
>> on the remote side isn't receiving data, OR that the server is trying to
>> prompt you somehow but you are not seeing that prompt, which is unlikely
>> but I've seen weirder, I'm sure.
>>
>> Which leads me to still suspect as Andrew Kember mentioned that X11 might
>> be getting in the way, or some other SSH option causing the client to wait
>> for the server to supply something and the two are in disagreement. Once
>> sanitized, could you send the contents of ~/.ssh/config (or, look there to
>> see if there is any mention of xauth or X11 ?) I most often don't have
>> anything in that config, so if it's heavily populated, you might need to
>> weed around it.... or, try renaming it temporarily so that it does not take
>> effect.
>>
>>
>> Note that if you are somehow trying to include ssh-copy-id inside as a
>> recipient in a pipe, it will play silly diggers with you, so don't pipe
>> anything into the script.
>>
>>
>> Good luck, cod speed.
>>
>>
>>
>> ===
>> Tai Kedzierski
>>
>> EdLUG Maintainer: https://edlug.gitlab.io/
>>
>> Edinburgh Language Meetup Organiser
>> https://www.meetup.com/Edinburgh-Language-Exchange-Meetup-Group/
>>
>> *Open Source Free Software is a matter of liberty, not price.*
>> https://www.fsf.org/about/what-is-free-software
>>
>>
>> On Tue, 30 Mar 2021 at 16:05, Justin B Rye <justin.byam.rye at gmail.com>
>> wrote:
>>
>> Robert McWilliam wrote:
>> > On Tue, 30 Mar 2021, at 13:09, Justin B Rye wrote:
>> >>> pstree -sup $(ps aux | grep sshd |  awk '{print $2}' | sort -n | head
>> -n 1)
>> >>>
>> >>
>> >> As a general rule of thumb, any complicated pipeline like that is
>> >> really a job for pgrep (which you probably get in the same package as
>> >> ps).  The above simplifies down to
>> >>
>> >>  pstree -sup $(pgrep sshd)
>> >
>> > You've thrown away a bit too much of the pipeline there: pgrep will
>> > give multiple results if there are SSH sessions and only want one for
>> > pstree so need the head part (and possibly the sort - I think ps and
>> > pgrep will give processes in order of PID without having to sort but
>> > chucking sort in the pipeline was quicker than checking).
>>
>> When you want the oldest, that's "pgrep -o sshd"; taking the lowest
>> number will mess up if the PIDs wrap around.  Mind you, I was
>> surprised by how hard it has become to do this - I hadn't previously
>> noticed that /proc/sys/kernel/pid_max has gone up from 32,768 on my
>> old stable desktop to 4,194,304 on my testbed machine!
>>
>> [...]
>> > Yes, just explaining where to manually copy the PID from is probably
>> > easier, but where's the fun in that :)
>>
>> I hope you'll forgive me my addiction to shell golf then!
>> --
>> Justin B Rye
>> http://jbr.me.uk/
>>
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