[Twg] [Discuss] [Lustre-devel] your opinion about testing

[Bruce Korb]

Hi,

On 4/30/12 3:37 PM, Nathan Rutman wrote:
>> 
>> It is not immediately clear how this fixes anything.  Such a facility
>> built into lnet needs to have exactly the same configuration issues as
>> ssh, munge, or whatever.  If it DOESN'T have the same issues, then it
>> sounds like it would be a very serious security risk.
>What it fixes is the ease of testing, by not requiring a separate
>communication path outside of LNET.  No router problems, no ssh'isms; if
>your client can talk to your servers, you're good to go.
>Obviously it doesn't resolve any security issues, and may introduce new
>ones.

It would introduce new ones.  By the time you are done addressing them,
you've
likely spent the effort required to set up ssh daemons.  For folks that
find
it difficult to configure, perhaps make a separate "lustre-testing" package
that does all the configury necessary to set up ssh for a specific testing
user.
I think developing that would be far easier than rolling your own new
mechanism.

>
>> 
>> Such a feature needs to at least be off by default and only enabled by
>>a 
>> human deciding that such a remote-access feature is acceptable.
>Agreed. Hopefully it might be easier to qualify a particular upcall
>program as "safe",

Installing the package would be a good human indicator.
You'd want such a package to be easy to turn off, too,
so it is only operational when testing is known to be active.

> rather than allowing arbitrary code execution as ssh does,

ssh can be constrained.  Constrain it to a particular testing user.
Over time, that user could have a testing harness shell that constrains
the command set however you like.  Having done this, I can say I found
it fairly trivial.