Re: moving from raw chunks to cooked files

On Wed, Aug 25, 2010 at 3:43 PM, Aleksander Kamenik < aleksander@krediidiinfo.ee> wrote: > Hi, > > We're running Suse Linux Enterprise Server on x86 and with the latest > SLES11SP1 release notes comes this announcement: > > "The RAW devices are deprecated and will be removed with one of the next > Service Packs or SUSE Linux Enterprise Server 12." > > I'm about to reinstall Informix onto new drives so might as well migrate to > cooked files. > > What filesystem is recommended? Are there any significant performance > issues nowadays? > > Currently I have two raw devices which contain a total of 18 chunks. I > would like to see them as 18 files on four different drives/partitions after > the migration. I can't find any documentation on migrating to cooked files. > Is this even possible? > > Using Informix 11.50.UC7. > > Regards, > > Aleksander Kamenik > System Administrator > Krediidiinfo AS > an Experian Company > Phone: +372 665 9649 > Email: aleksander@krediidiinfo.ee > > http://www.krediidiinfo.ee/ > http://www.experiangroup.com/ > > Hello, Yes, it's possible. You should use a non journalled filesystem (search for recent discussions on this in the mailing list). You should also activate DIRECT_IO in your instance configuration. Regarding the "migration" itself there isn't really too much to do.... It really depends on what you're about to do... Let see. You talk about "installing Informix on two new drives". What exactly does it mean? Are you talking about just the product installation or the data chunks? How were you plan to move the data if you were going to use RAW devices? An Informix backup/restore or an offline "dd" or anything else? The idea is that you need to create the new files (after the filesystem creation a simple "touch/chmod" will do.... Then you need to copy the data in a consistent way.... And finally you need to tell your instance that it should be using the new files and not the old ones... If you're using symbolic links for your current RAW devices, you just have to point them to the new files... Regarding ways to copy data.... several options: 1- OFFLINE with dd OS command 2- OFFLINE with backup/restore (using the rename option to move the chunks, or simply changing the links) 3- ONLINE with something that can synchronize the files "online".... This can be tricky or challenging.... I've used it with logical volume managers (between two raw devices, followed by a short engine stop to change the links). You could also use Informix mirror ability.... I'd have to check the "after synchronize steps".... Tell us more about your plan of activities (forgetting the move from RAW to filesystem) and then we can give you more help Regards. -- Fernando Nunes Portugal http://informix-technology.blogspot.com My email works... but I don't check it frequently...