[Netconf] Does <discard-changes> do the same thing as <copy-config>-ing 'running' to 'candidate'?

[Attila Vangel <[e-mail]>]

Hi,

N00b question on netconf. Could somebody please clarify?

1. Does <discard-changes> (
https://tools.ietf.org/html/rfc6241#section-8.3.4.2) have totally the same
effect as <copy-config>-ing 'running' to 'candidate'?

"This operation discards any uncommitted changes by resetting the
   candidate configuration with the content of the running
   configuration."

If so, was it introduced as a shorter alternative of copying?
If not, what is the difference between them?

2. I got confused because I watched a tutorial on youtube which used both
commands, first <discard-changes> before locking any config datastores, and
<copy-config>-ing 'running' to 'candidate' after locking these datastores.
(The assumption in this example is that the device supports 'candidate'.)

3. For the first time I was puzzled why to do <discard-changes> before
doing any locking, but then I read in the RFC that lock would fail if
'candidate' was "dirty" (https://tools.ietf.org/html/rfc6241#section-7.5):

A lock MUST NOT be granted if any of the following conditions is
      true:

      *  A lock is already held by any NETCONF session or another
         entity.

      *  The target configuration is <candidate>, it has already been
         modified, and these changes have not been committed or rolled
         back.

      <...>

But still I am not sure about 1. If these commands do the same thing, using
<copy-config> in this tutorial was just for showcasing doing it yet another
way in 2.?

(I was not sure whether to share the link for the tutorial, maybe it
would look like as advertising the company/author who did the
tutorial.)

Best regards,
Attila