[Swift-devel] Re: more ftp errors running terminable->tg uc

[Michael Wilde]

i) proposal sounds good to me

ii) Mihael is on pseudo-vacation (supposed to be real vacation at the 
moment, but he is being a great guy to help launch an i2u2 release that 
slipped).  So lets wait for Mihael to weigh in. Only thing I can offer 
is once i2u2 release is live and stable, fix gridftp next, modulo 
vacation preferences).

- Mike


On 3/14/08 6:14 PM, Ben Clifford wrote:
> I have dug some more into this.
> 
> The cog gridftp provider enables data channel reuse when talking to 
> gridftp servers that report exactly version 2.3.
> 
> Some of the sites that I am testing against report that version. Some 
> report version 2.5.
> 
> The sites which are version 2.3 fail to run test workflow '130-fmri' in 
> the tests/language-behaviour directory. The sites which are not 2.3 do not 
> exhibit this problem.
> 
> This happens submitting from both tg-login1.uc.teragrid.org and from 
> terminable.ci.uchicago.edu
> 
> On terminable:
> 
> If I change the cog gridftp provider to enable gridftp data channel reuse 
> for version 2.5 too, then the 2.5 sites also break.
> 
> If I disable data channel reuse entirely (which appears to need a source 
> code change) then all site tests work ok.
> 
> There are two separate issues here:
> 
> This needs fixing in general, presumably in cog. At the moment, I'm not 
> particularly inclined to spend large amounts of time learning how the cog 
> ftp provider works when potentially mihael could look at it. However, its 
> unclear how much time mihael has to work on this, given his other projects 
> and I have no particular belief that it will be fixed any time soon.
> 
> In a Swift-specific context, I'm happy for data-channel reuse to be turned 
> off for now (eg until someone figures out what is up at the cog level) - 
> its already not used for any recent gridftp server (i.e. v2.5) such as 
> tg-gridftp.uc.teragrid.org.
> 
> No one has reported this as a problem in the wild (yet). I suspect test 
> 130-fmri is especially good at exhibiting this problem.
> 
> I think therefore that this should not be a release-stopped for 0.4; but 
> that should anyone actually come across it in the wild we should rapidly 
> put out a 0.4.1 or a 0.5 with data channel caching disabled.
> 
> I would appreciate commentary on:
> 
>    i) the above release proposal
> 
>   ii) the likelihood that Mihael will have time to look at this and when 
>       that would happen (which is essentially the question - do I have to 
>       go learn the guts of the gt2 cog provider?)
>