[mapserver-users] Dynamically update layers without service interruption

[Björn Harrtell]

Thank you, this makes quite alot of sense. I'll try to apply it to my case.

2009/12/10 Stephen Woodbridge <woodbri at swoodbridge.com>:
> The key to this is to minimize the time that the data and mapfile are
> potententially out of sync or the time a file might be being updated so that
> it is in a state of flux that might cause an error if a request tries to
> read the file while it is being updated.
>
> I have managed this in the past with parallel data trees and a symbolic link
> on Linux.
>
> /path/to/data/
> /path/to/data/imagesA
> /path/to/data/imagesB
> /path/to/data/images -> imagesA or imagesB
>
> the map file points to /path/to/data/images and that is a symbolic link to
> either imagesA or imagesB, for example lets say imagesA
>
> So the update process would be something like:
>
> # sync your A and B trees
> rsync -s imagesA/* imagesB/.
>
> # update the images in imagesB and the mapfile in imagesB
>
> # make imagesB live
> (cd /path/to/data/; rm images; ln -s imagesB images)
>
> # if you want to rollback to imagesA
> (cd /path/to/data/; rm images; ln -s imagesA images)
>
> Hope this helps,
>  -Steve W
>
> Dan Little wrote:
>>
>> Yes, it's a matter of how you do your data management.
>>
>> Generally, if you're using MapServer in CGI mode you can update the
>> data, or the mapfile, and the next time a request comes in, it will
>> see the updated version of your image.
>>
>>
>>
>> ----- Original Message ----
>>>
>>> From: Björn Harrtell <bjorn.harrtell at gmail.com> To:
>>> mapserver-users at lists.osgeo.org Sent: Mon, December 7, 2009 3:11:36
>>> PM Subject: [mapserver-users] Dynamically update layers without
>>> service interruption
>>>
>>> Is it possible to dynamically add and/or update layer definitions
>>> that also might involve updates to the underlying data without
>>> *any* service interruption? I'm primarily interested in this use
>>> case when using raster layers.
>>>
>>> I have indications that service interruptions can happen but cannot
>>>  verify yet. I found
>>> http://www.mapserver.org/development/rfc/ms-rfc-44.html#rfc44 describing the
>>> feature of dynamic updates (I assume?) but no
>>> mention about if service interruption can be expected and/or how to
>>> avoid it.
>>>
>>> Regards,
>>>
>>> Björn Harrtell _______________________________________________
>>> mapserver-users mailing list mapserver-users at lists.osgeo.org
>>> http://lists.osgeo.org/mailman/listinfo/mapserver-users
>>
>>
>>
>>
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>
>