[Engine-devel] [Design for 3.2 RFE] Improving proxy selection algorithm for Power Management operations

[Dan Kenigsberg]

On Sun, Nov 11, 2012 at 06:18:53AM -0500, Eli Mesika wrote:
> 
> 
> ----- Original Message -----
> > From: "Eli Mesika" <emesika at redhat.com>
> > To: "Itamar Heim" <iheim at redhat.com>
> > Cc: "engine-devel" <engine-devel at ovirt.org>
> > Sent: Friday, November 9, 2012 12:06:05 PM
> > Subject: Re: [Engine-devel] [Design for 3.2 RFE] Improving proxy selection algorithm for Power Management operations
> > 
> > 
> > 
> > ----- Original Message -----
> > > From: "Itamar Heim" <iheim at redhat.com>
> > > To: "Eli Mesika" <emesika at redhat.com>
> > > Cc: "engine-devel" <engine-devel at ovirt.org>, "Michael Pasternak"
> > > <mpastern at redhat.com>, "Simon Grinberg"
> > > <sgrinber at redhat.com>, "Dan Kenigsberg" <danken at redhat.com>
> > > Sent: Friday, November 9, 2012 12:02:37 PM
> > > Subject: Re: [Engine-devel] [Design for 3.2 RFE] Improving proxy
> > > selection algorithm for Power Management operations
> > > 
> > > On 11/09/2012 10:52 AM, Eli Mesika wrote:
> > > 
> > > >> >
> > > >> >  > FenceWrapper
> > > >> >
> > > >> >i understand danken suggested going this way, rather than than
> > > >> >another
> > > >> >instance of vdsm.
> > > >> >is vdsm only calling these scripts today and all logic is in
> > > >> >engine,
> > > >> >or
> > > >> >does vdsm has any logic in wrapping these scripts (not a
> > > >> >blocker
> > > >> >to
> > > >> >doing FenceWrapper, just worth extracting that logic from vdsm
> > > >> >to
> > > >> >such a
> > > >> >script, then using it in both. i hope answer is 'no logic'...)
> > > > vdsm has some logic that maps between the call passed to it from
> > > > engine and the actual parameters generated for the script.
> > > > AFAIK, this logic only "builds" the correct arguments for the
> > > > command according to the agent type
> > > >
> > > 
> > > can we extract it to an external wrapper?
> > > I'd hate to fix bugs/changes twice for this.
> > 
> > I'll check it with danken on SUN
> 
> Well, looked at it a bit , the VDSM code is in fenceNote function in API.py
> What I think is that we can exclude the fenceNote implementation to a separate fence.py file and call it from the API.py
> Then we can use one of the following in Java to call the method from fence.py
> 1) jython
> 2) org.python.util.PythonInterpreter
> 
> See http://stackoverflow.com/questions/8898765/calling-python-in-java
> 
> danken, what do you think ?

BTW, no one has promised the the fence script is implemented in Python

$ file `which fence_ipmilan `
/usr/sbin/fence_ipmilan: ELF 64-bit LSB executable...