On Tue, Nov 18, 2014 at 4:47 PM, Brady, Mike <mike.br...@devnull.net.nz>
wrote:
> On 2014-11-16 05:36, Ana Emília M. Arruda wrote:
>
>> Hi Mike,
>>
>> Despite that the white paper tell us about having "Maximum Concurrent
>> Jobs = 1" in device configuration. I think this could make sense when
>> using stand alone devices in a group as you have in the white papers.
>> When using autochangers, it is much better you use the "Maximum
>> Concurrent Jobs" in storage definitions, so Bacula will use the second
>> drive when the first one is in use. Maybe this way you will not have
>> the problem of the second job having to wait for a drive.
>>
>
> I do not understand what you mean.
>
> What do the white papers say about having "Maximum Concurrent Jobs = 1"?
> I can not find anything.
>
> I do have Maximum Concurrent Jobs set in the Storage definition.
>
I saw it too in your device configuration:
Device {
Name = FileChgr1-Dev1
Drive Index = 0
Media Type = File01
Archive Device = /bacula_storage/FileDevice
LabelMedia = yes;
Random Access = Yes;
AutomaticMount = yes;
RemovableMedia = no;
AlwaysOpen = no;
Maximum Concurrent Jobs = 1
VolumePollInterval = 5s
Autochanger = yes
}
> And the job is not waiting for a device. The second device can not find
> an available volume. But this only happens when a schedule first starts.
> Once the second device tries to get a volume again after a 5 minute timeout
> everything works as expected. That is, in this case two devices each with
> a different volume mounted from the same pool with one job writing to each
> device at a time.
>
> As I replied to Josh a short while ago, I do not believe that the volume
> selection and auto creation/labeling operations are thread safe. There may
> well be configuration options that reduce/work around the issues, but I do
> not currently have the time to do the necessary testing, so I am no longer
> pursuing this.
>
>
>> Now I was wondering if you have just the IncPool pool? For all your
>> jobs and for full, diff and inc backups? I would suggest you having
>> them separately for admin purposes. As your number of clients and
>> backups increase, maybe it could become a little difficult to manage a
>> so large and diversified pool.
>>
>> I have Inc, diff and full pools. The diff and full pools just aren't
> relevant to this issue.
>
> Bacula is a very very flexible backup tool and will let you do
>> configurations that will not make sense at the end, but it will allow
>> you do it.
>>
> So I have found many times.
>
>
>> Another point here is about "RemovableMedia = no;". The white papers
>> set it to "yes". I'm not so sure if this directive is considered in a
>> virtual autochanger configuration. I had seen it set to "no" or "yes"
>> interchangeably. Maybe this could not tamper with your problem, but
>> for me it makes more sense to use it set to "yes" like it is in the
>> white papers.
>>
>>
> For Autochanger devices the "Best Practices for Disk Based Backup" and
> "Disk Backup Design" white papers have RemovableMedia set to yes in one of
> them and no in the other (can't remember which way around it is). This may
> well work around the race condition for volume selection by having the
> device search for a volume when the "Can not find an available volume"
> condition occurs.
>
> I do not have a lot of volumes so this may well work for me, but if there
> are thousands of volumes in a device directory then this may impact
> performance significantly.
>
> Do you have "prefer mounted volumes" set to no in your jobs
>> definition? It is recommended if you are using multiple devices and
>> one pool.
>>
>
> I do not have this set because of the warnings against it in both the
> manual and one of the white papers.
>
But this is recommended when using multiple devices (autochanger or stand
alone) and one pool.
>
> Thanks for your suggestions.
>
You´re welcome.
Best regards,
Ana
------------------------------------------------------------------------------
Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server
from Actuate! Instantly Supercharge Your Business Reports and Dashboards
with Interactivity, Sharing, Native Excel Exports, App Integration & more
Get technology previously reserved for billion-dollar corporations, FREE
http://pubads.g.doubleclick.net/gampad/clk?id=157005751&iu=/4140/ostg.clktrk
_______________________________________________
Bacula-users mailing list
Bacula-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/bacula-users
