Re: [Duplicity-talk] duplicity 0.7.02, freebsd and sftp backend -- how to further debug.

[edgar . soldin]

On 05.05.2015 15:43, Dirk-Willem van Gulik wrote:
> 
>> On 03 May 2015, at 20:55, address@hidden wrote:
>>
>> On 03.05.2015 19:16, Dirk-Willem van Gulik wrote:
>>>
>>>> On 03 May 2015, at 18:58, address@hidden wrote:
>>>>
>>>> On 03.05.2015 18:37, Dirk-Willem van Gulik wrote:
>>>>> ------------ ------------ ------------ ------------ ------------ ——————
>>>>>
>>>>> On a (new) 0.7.02 upgrade/install; which works fine with a file:/// 
>>>>> backend to /tmp as a test — we’re finding that it hangs ‘forever’ on 
>>>>> ‘sftp’.
>>>>>
>>>>> sftp itself works fine; and when we place a few files there - we can see 
>>>>> in the output that they are nicely seen; and ignored (as is the .ssh 
>>>>> directory with the right authorized_keys magic).
>>>>>
>>>>> Below is the command used and the output. Any suggestion as to where/how 
>>>>> to start debugging this ?
>>>>>
>>>>> The main change with prior version/use is a sharply increased volume and 
>>>>> going to version 0.7.02 (as python needed to be upgraded).
>>>>>
>>>>
>>>> the keepalive & EOFError parts suggest that your ssh connection is dropped 
>>>> after a while. check if that is disabled for some reason in your ssh 
>>>> server settings.
>>>>
>>>> alternatively use the old pexpect ssh backend.
>>>>
>>>
>>> Thanks - debugging with this (Setting timeout to a few hours) and looking 
>>> at tcpdump suggests that after
>>>
>>>     ssh: [chan 1] open('/duplicity-full.20150503T171238Z.vol1.difftar.gpg', 
>>> 'wb')
>>>     ssh: [chan 1] open('/duplicity-full.20150503T171238Z.vol1.difftar.gpg', 
>>> 'wb') -> 39323765383430333130396635343637
>>>
>>> no traffic is sent at all but for the occasional:
>>>
>>>     ssh: Sending global request "address@hidden"
>>>     ssh: Sending global request "address@hidden"
>>>     ssh: Sending global request "address@hidden
>>>
>>> requests. It is almost as if duplicity is not streaming at all. An 
>>> identical command to ‘file://' shows the files getting created and 
>>> sent/written just fine.
>>>
>>
>> well, 
>>
>> 1.does '--ssh-backend pexpect' at least work as expected?
> 
> Well - I believe/from the code I gather that ‘-ssh-backend' is retired in 
> 0.7.02; but using pexpect+sftp://address@hidden does the trick.
> 
> And yes - it works as expected. Sorry for not being clear there.

hehe.. my commit and already forgot about it ;)

>> 2. what do you mean by 'setting timeout’?
> 
> The client-no data timeout values in sshd; as well as kernel TCP setting to 
> avoid the TCP conncetion getting closed that way; as well as ssh-paramiko’s 
> globals.timeout driven timeout.

ic
 
>> 3. does duplicity come up with a stacktrace _and_ still hang using paramiko?
> 
> The connection hangs (strace shows no data sent on that file descriptor ever 
> (after an successful ls earlier) — until the stacktrace at which point all 
> fd’s are closed and things are rolled up.
> 
>> 4. what is your paramiko version?
> 
> Set to 1.14.0.
> 

you may wanna try their latest greatest, even if you might have to install it 
manually.

..ede/duply.net