Server refused to start a shell/command (Buildroot - RPi)

[Kevin Hill]

After logging in successfully the following log messages are indicative 
of my problem:

pty_allocate: openpty: No space left on device
No pty was allocated, couldn't execute
Exit (root): Exited normally.

PuTTY gets the messages:
Server refused to allocate pty
Server refused to start a shell/command.

So how do I fix this?
Which device is it talking about?
My buildroot system is running from initramfs.

Thanks,
Kevin

On 2015-01-13 13:35, Matt Johnston wrote:
> Hi,
>
> If you run “dropbear -F -E” (kill the existing server process first)
> then it will run in the foreground and print logging. That should
> suggest what’s going wrong. Alternatively it might already be logging
> to somewhere in /var/log depending if syslog is running.
>
> Cheers,
> Matt
>
>> On Tue 13/1/2015, at 9:24 pm, dropbear at procountsoftware.co.uk wrote:
>>
>> I have a minimalistic buildroot system for the Raspberry Pi and 
>> would like
>> to add a dropbear ssh server to it that is started and is available 
>> from
>> boot, but for now I'm just trying to enable it manually and I'm 
>> having a
>> few problems.
>>
>> I enabled dropbear within 'make menuconfig' and rebuilt buildroot. 
>> It
>> downloaded dropbear 2013.58 which I know is a little old, but it 
>> should
>> still work, right?
>> After booting my new system I didn't use S50dropbear itself but 
>> tried to do
>> things manually. I created /etc/dropbear and within there I created 
>> the
>> keys necessary for dropbear using:
>>
>> dropbearkey -t rsa -f dropbear_rsa_host_key
>> dropbearkey -t dss -f dropbear_dss_host_key
>>
>> Then I executed dropbear (no arguments) and I could see it in the 
>> process
>> list.
>>
>> When I tried to connect to it from Putty, I got the following error:
>> "Server refused to allocate pty" which I discovered was possibly due 
>> to not
>> having a suitable mountpoint.
>> So I added the following entry to FSTAB (as per a google post I 
>> found):
>>
>>     none            /dev/pts        devpts        gid=5,mode=620    
>> 0 0
>>
>> Now the error has changed to "Server refused to start a 
>> shell/command" and
>> I haven't been able to find a solution. I can connect to the Pi 
>> using
>> WinSCP over SCP fine, but I really want a command shell using PuTTY.
>>
>> This may be more to do with my minimalistic buildroot configuration 
>> than
>> anything else, but this is my first buildroot build so I'm a bit of 
>> a
>> newbie. My starting point was the buildroot configuration used to 
>> create
>> the RPi NOOBS recovery program.
>>
>>
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