Re: moving from raw chunks to cooked files
On Wed, Aug 25, 2010 at 10:00 PM, Fernando Nunes <domusonline@gmail.com>wrote: > > > 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... > Well.... I'm now feeling officially stupid... Somehow I missed all the discussion going on... I think all that I wrote was already detailed... Sorry... -- Fernando Nunes Portugal http://informix-technology.blogspot.com My email works... but I don't check it frequently...