[j-nsp] CLI/OP Script Interaction

[Judah Scott]

Got it.   Thanks for taking the time to explain all that.

On Fri, Oct 23, 2009 at 11:13 AM, Phil Shafer <phil at juniper.net> wrote:

> Judah Scott writes:
> >What is a transient change?
>
> Here's some (long-ish) explanatory text:
>
>   You can use commit scripts to generate transient changes, which are
>   changes that are not saved in the candidate configuration but are
>   propagated to the components of the system.  Transient changes are
>   made to the copy of the database that is exported to JUNOS
>   components, but not to the candidate or committed configuration
>   databases.  This allows configuration changes to be transient, in the
>   sense that they are not preserved by the system.
>
>   You can use transient changes to eliminate the repetition of
>   well-known policies, thus allowing these policies to be performed
>   implicitly.  For example, if MPLS must be enabled on every
>   ISO-enabled interface, the change can be transient, so that the
>   repetitive or redundant configuration data need not be carried and
>   displayed to the user.
>
>   The syntax for transient changes is nearly identical to that for
>   permanent changes.  To make transient changes to the configuration,
>   include a <transient-change> element within the commit-script-output
>   element.  The <transient-change> element contains the desired change
>   in the format required by a JUNOScript <load-configuration> RPC
>   operation.  For example:
>
>       <transient-change>
>         <system>
>           <host-name>rdu-03-42</host-name>
>         </system>
>       </transient-change>
>
>   To enable transient changes, you must configure the
>   "allow-transients" statement at the [system scripts commit] level of
>   the configuration hierarchy.  Without this statement, the UI will
>   ignore transient changes.
>
>   To view and test transient changes, use the "show | display
>   commit-scripts" command.  This command displays the post-commit
>   scripts contents of the database without actually changing the
>   database.  It displays both transient and standard changes.
>
>       [edit]
>       cli# show | display commit-scripts
>
> Actually, I think emitting transient changes without allow-transients
> is now a commit error.
>
> >Also do you mean an op script can trigger a commit-script
> >to make transient changes? (It looks like the second "op script" was meant
> >to say "commit-script."
>
> I mean that you could have a script that asks the user some questions,
> builds some config from it in the form of an apply-macro, loads
> that config, and performs a "commit-configuration" operation.  As
> part of that commit, any commit scripts (that are configured) will
> be run, and those scripts could generate transient changes from
> that apply-macro.
>
> So your op script can't make transient changes, but it can performs
> commits, which will trigger commit scripts that can generate transient
> changes.
>
> Thanks,
>  Phil
>