| Title: | Oracle | 
| Notice: | For product status see topics: UNIX 1008, OpenVMS 1009, NT 1010 | 
| Moderator: | EPS::VANDENHEUVEL | 
| Created: | Fri Aug 10 1990 | 
| Last Modified: | Fri Jun 06 1997 | 
| Last Successful Update: | Fri Jun 06 1997 | 
| Number of topics: | 1574 | 
| Total number of notes: | 4428 | 
    
    	Hi people:
    
       A simple cuestion.
       
       I have a customer that he asks me about raw devices.He has Oracle
       database using raw devices.
       Oracle said that Digital Unix utilises a 64k operating system header
       at the begining of each raw device.
       
       I have tested this with dd comand.
      
       dd if=/etc/inittab of=/dev/rrz5c 
    
       dd writes in a block 0 if not labeled 
                     or 
       block 1 if the disk is labeled using in dd command seek=1
    
       Is true that Digital Unix uses a 64k or is a caracteristic of
       Oracle?
       
       Thanks,in advanced.
       Helps will be welcome.
    
       Francesc
    
    
| T.R | Title | User | Personal Name | Date | Lines | 
|---|---|---|---|---|---|
| 1571.1 | Re: raw devices 64k | AMCUCS::KKDAS | Let's Train The Trainers | Mon Jun 02 1997 14:34 | 9 | 
| This is an Oracle implementation to avoid confusion. Unlike other databases (Informix and Sybase) Oracle doesn't allow an offset in raw disks, therefore, datafile creation would fail if a partition is used that starts from block 0 (default partitions 'a' and 'c' of a labeled disk) but it will succeed for other partitions. Introducing a default offset of 64K eleminates the confusion. /KK/ | |||||
| 1571.2 | Thanks | BARNA::DSMAIL | Tue Jun 03 1997 10:03 | 3 | |
|     
    
    	Thanks.
 | |||||
| 1571.3 | Oracle version ? | NNTPD::"[email protected]" | qcav01::srinath | Tue Jun 03 1997 10:22 | 12 | 
| Hi KK Thanks for that .1 info - But i have faced problems when using the 'a' partition as raw. The Oracle version was 7.1.6 and Digital Unix 3.2c, any high volume i/o on that partition would create failure of the datafile. Putting a redolog(raw) in that partition was fatal for me on one occasion. Any ideas why this happened?. 73's srinath [Posted by WWW Notes gateway] | |||||