[DRBD-user] DRBD, Informix and raw devices

[Clive Eisen]

Christof Amelunxen wrote:

>Hi Clive,
>
>thanks for your reply.
>
>Am Mo, den 31.10.2005 schrieb Clive Eisen um 16:17:
>  
>
>>>we plan to use DRBD and heartbeat to cluster an Informix DB and we would
>>>like to use raw devices to store the data on.
>>>
>>>Has anybody ever tried using Linux raw devices on top of DRBD or could
>>>one of the technical experts around tell me if this is possible at all?
>>>
>>> 
>>>
>>>      
>>>
>>I have done it as a demo, not in production.
>>
>>It works fine with raw and heartbeat although depending on your distro 
>>you may have to hack the 'raw' script to actually work
>>
>>http://groups.google.co.uk/group/novell.support.suse.linux.professional/browse_thread/thread/62b8da97916987dd/b11209c7c384fa9e?lnk=st&q=%22clive+eisen%22+raw&rnum=4&hl=en#b11209c7c384fa9e
>>    
>>
>
>Is it necessary to have the raw devices be managed by heartbeat? I was
>thinking about binding the raw devices statically to the drbd
>major/minor numbers. 
>
>  
>
IIRC I couldn't bind raw on the drbd secondary, only on the primary, 
which IMHO makes sense.

Therfore raw had to be managed by heartbeat

>>Later informix versions open the chunks as 'raw' without you having to 
>>go through these hoops, and will also use KAIO if possible
>>    
>>
>
>But does that make any difference in practice? At least for me, the
>"drbd administrator"?
>
>  
>
Yes because you don't have to have raw in your haresourses - it's no big 
deal, but just one less thing to get working

--
Clive