Re: [Bacula-devel] edit_job_codes with Migrate/Copy Jobs

[Dan L. <da...@la...>]

On 11/26/2010 11:01 AM, Dan Langille wrote:
> On 11/26/2010 2:41 AM, Eric Bollengier wrote:
>> Hello Dan,
>>
>>
>> On Friday 26 November 2010 04:53:52 Dan Langille wrote:
>>> Background: A copy/migrate job has at least two Volumes:
>>>
>>>     * the Volume[s] for the original Job (at least one)
>>>     * the Volume[s] for the new Job (i.e. Copy/Migrate) (at least one)
>>>
>>> My problem: When a copy/migrate job includes a RunAfterScript, the %v
>>> parameter passed into the script is *always* the source Volume; the
>>> destination Volume cannot be passed in.  This means the script cannot
>>> know the destination volume, which is something I want.[1]
>>>
>>> Proposal: add a %V (capital V) option to edit_job_codes in lib/util.c
>>
>> I agree, this is a nice addition.
>>
>>> Issue: The volume name we need is contained in mig_jcr, which is created
>>> within migration_cleanup().  I know this based upon the job output (see
>>> below)[2][3]
>>>
>>> My initial attempt failed.  See the attached patches.  The problem I
>>> encountered may not be related to the patch.  The tape was having a seek
>>> problem (which has since gone away after switching to a new tape and
>>> restarting the tape library).  If the feedback here indicates I should
>>> try again, I will.  I first want to ensure I'm not taking the wrong
>>> approach.
>>
>> We have a callback mechanism that permits to add per daemon job code
>> variables, so instead of modifying the edit_job_code(), you can add specific
>> variables to the Director in dird_conf.c job_code_callback_filesetname() (it's
>> a good idea to change the callback name to something less specific).
>
> Ugh.  It appears to be a dead end. jcr->mig_jcr has no value in
> job_code_callback_filesetname(), thus, we can't grab the right Volume name.

Off list, Eric and I spoke via IRC regarding this issue.  I now know why 
jcr->mig_jcr has no value.  The clearing occurs in src/dird/migrate.c 
migrate_cleanup():

    if (jcr->mig_jcr) {
       free_jcr(jcr->mig_jcr);
       jcr->mig_jcr = NULL;
    }

If we comment out this code, which is not the ideal solution, amended 
job_code_callback_filesetname() works.

Perhaps an ideal solution involves clearing jcr->mig_jcr within 
src/lib/jcr.c b_free_jcr(), but my initial attempts there fail:

    if (jcr->mig_jcr) {
       b_free_jcr(file, line, jcr->mig_jcr);
       jcr->mig_jcr = NULL;
    }

because:

jcr.c: In function 'void b_free_jcr(const char*, int, JCR*)':
jcr.c:492: error: 'class JCR' has no member named 'mig_jcr'

Again, bitten by the #ifdef....

But... progress is being made.  :)


-- 
Dan Langille - http://langille.org/