[Pacemaker] Re: [Linux-HA] the crm command line interface

Dejan Muhamedagic dejanmm at fastmail.fm
Fri Sep 5 12:38:07 EDT 2008


Hi Serge,

On Fri, Sep 05, 2008 at 09:42:41AM -0600, Serge Dubrouski wrote:
> Hello -
> 
> It's a really great tool. Great job!

Thanks.

> Here are my expirience
> (pacemaker-0.6.5-2.2 + Heartbeat 2.1.3-23.1:
> 
> Nodes.
> 
> 1. Status and Show Node show the exactly the same information. Even
> when you provide node name in show command it shows all nodes. Is it
> supposed so?

No. Actually, I'm looking for input here. Don't exactly know
what's interesting for users. There are two kinds of information:
provided by the CIB (node type and node attributes) and by
crmadmin (if the node's online and if it is DC).

> cib.
> 
> Couldn't test it because crm_shadow wasn't found. Looks like it's a new tool.

Yes. That's a very useful new thing provided by Andrew. It
basically allows you to test the configuration out of the
cluster.

> Resource.
> 
> 1. Status without parameters shows a list of resources but doesn't
> show the real status of them onlinr/stopped.

Hmm. Strange. Here it says:

crm(live)# resource status
Resource Group: g1
    ip2 (ocf::heartbeat:IPaddr) Started 

> 2. It's not clear how to migrate a resource to a specific node it it's
> possible at all.

The help is still lacking. You can do migrate:

resource migrate rsc node
or
resource migrate rsc

> 3. It would be good if param resource show was able to show all
> parameters for a given resource.
> 
> 4. Again would be good failcount resource was able to show failcounts
> for all nodes

I'll see if I can implement that. Though that kind of stuff
should be done at the configure level:

configure show rsc

> Configure.
> 
> ERROR: CIB release '2.1' is not supported
> ERROR: bad cib

Unfortunately, the CIB syntax changed, so the program supports
only the one which will be in pacemaker 1.0 (now: 0.7). It's a
pity because this part is the most interesting.

> Will try this part later when I upgrade it to the latest version,
> though I think that you shall consider support for old releases as
> well.

I am. Though I'm rather low on time resources.

> Options.
> 
> 1. Help message for skill-level command doesn't say what are possible
> options. Entering "skill-level high" crashes the program:

Just did an update: if you type a command without args or too
many args, it should print usage.

> Traceback (most recent call last):
>   File "./crm", line 3117, in <module>
>     parse_line(levels,shlex.split(inp))
>   File "./crm", line 3037, in parse_line
>     rv = d() # execute the command
>   File "./crm", line 3036, in <lambda>
>     d = lambda: cmd[0](*args)
>   File "./crm", line 255, in set_skill_level
>     if skill_level in skill_levels:
> NameError: global name 'skill_levels' is not defined

Fixed.

Did I mention that it is most probably full of bugs :)

> 2. pager/editor/skill-level/user commands without parameters should
> show current values.

Right. That interface was done too hastily. It should perhaps
follow something like:

set param value
show param

> Thanks for the great job!

You're welcome.

Cheers,

Dejan

> Serge.
> 
> 
> 
> On Fri, Sep 5, 2008 at 8:59 AM, Dejan Muhamedagic <dejanmm at fastmail.fm> wrote:
> > Hi,
> >
> > Can't read XML? Then this may be something for you...
> >
> > For some time the command line interface for the CRM/Pacemaker
> > has been in the works. About one month ago I posted a draft
> > specification and user guide to the development list. There was
> > no response, so I assumed that everybody was happy with it ;-)
> >
> > As I got better grip on how the program could be used, the
> > specification changed accordingly during the development.
> >
> > The first release is already in the Pacemaker's development
> > repository. You can get it here:
> >
> > http://hg.clusterlabs.org/pacemaker/dev/raw-file/tip/tools/crm.in
> >
> > To run it, first replace @HA_VARLIBDIR@ with /var/lib or wherever
> > heartbeat/crm lives. Or compile and install the latest pacemaker
> > code. Andrew will probably soon make new rpms.
> >
> > The source of the current documentation:
> >
> > http://hg.clusterlabs.org/pacemaker/dev/raw-file/tip/doc/crm_cli.txt
> >
> > It is readable, but to produce an esthetically more pleasing
> > document, just process it with asciidoc to get PDF or HTML.
> >
> > CLI consists of two main parts: the management (resource
> > start/stop, node standby, and similar) and the configuration
> > part. There is a (very) small language with which it is possible
> > to specify the cluster configuration. This description is then
> > translated by the CLI into an XML which the CRM understands.
> >
> > The management may be used with all versions of heartbeat
> > v2/pacemaker, as it is using the external tools such as
> > crm_resource.
> >
> > The configuration part supports only the development version of
> > Pacemaker, i.e. it won't work with Pacemaker 0.6.x or Heartbeat
> > 2.1.x versions. If there's a too big an outcry, I may consider
> > fixing it to support the older releases as well.
> >
> > To start using it, read the document. If you can't (as most of
> > you probably won't), just start the program (type crm) and try to
> > manage with help.
> >
> > Some things are not implemented yet, but should be there soon
> > enough:
> >
> > - tab completion (this seems to me very important, so it is the
> >  first on the list)
> > - configuring cluster properties (crm_config)
> > - the "slow" resource configuration (the "enter" command)
> >
> > Suggestions are, as always, very welcome. If you have a good idea
> > on how to improve the usability, I'm all ears.
> >
> > Thanks,
> >
> > Dejan
> > _______________________________________________
> > Linux-HA mailing list
> > Linux-HA at lists.linux-ha.org
> > http://lists.linux-ha.org/mailman/listinfo/linux-ha
> > See also: http://linux-ha.org/ReportingProblems
> >
> 
> 
> 
> -- 
> Serge Dubrouski.
> 
> _______________________________________________
> Pacemaker mailing list
> Pacemaker at clusterlabs.org
> http://list.clusterlabs.org/mailman/listinfo/pacemaker




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