Hello! I have some questions about external journals. On a 4 disk software RAID 5 I have two big devices (one 60 GB, one 180 GB). I would like to give each an external journal on a 2 disk software RAID 1 device and use data=journal. The journal will get its own partition with mke2fs -O journal_dev /dev/mdwhatever. The used 6 harddrives are all IDE drives, they are connected through mainboard and additional ide controllers, each one as master (no slaves). My questions: How big should each of the journals be? Can I put both journals in one RAID 1 device (i.e. give both the same device=/dev/mdwhatever or should/must I put them in two different devices (which would have to be on the same two disks in any case) /dev/mdwhatever1 and /dev/mdwhatever2? Thanks in advance, Norman Schmidt. -- -- Norman Schmidt Institut für Physikal. u. Theoret. Chemie cand. chem. Friedrich-Alexander-Universitaet schmidt@naa.net Erlangen-Nuernberg
On Dec 21, 2002 16:03 +0100, Norman Schmidt wrote:> On a 4 disk software RAID 5 I have two big devices (one 60 GB, one 180 > GB). I would like to give each an external journal on a 2 disk software > RAID 1 device and use data=journal. > > How big should each of the journals be?Depends on what you are doing.> Can I put both journals in one RAID 1 device (i.e. give both the same > device=/dev/mdwhatever or should/must I put them in two different > devices (which would have to be on the same two disks in any case) > /dev/mdwhatever1 and /dev/mdwhatever2?Currently, you need to put them on different block devices. At some (probably distant) time in the future it will be possible to share an external journal among filesystems, but I don't think anybody is working on that yet. Cheers, Andreas -- Andreas Dilger http://sourceforge.net/projects/ext2resize/ http://www-mddsp.enel.ucalgary.ca/People/adilger/
Andreas Dilger schrieb:> On Dec 21, 2002 16:03 +0100, Norman Schmidt wrote: > >>How big should each of the journals be? > > > Depends on what you are doing.Mainly big files (pdfs of articles, diploma theses, images, films, music as well) of sizes from 1 to 800 MB and nightly full backups of other servers. Thanks so far, Norman. -- -- Norman Schmidt Universitaet Erlangen-Nuernberg _ cand.chem. Sysadmin Wohnheimnetzwerk RatNET _ // mailto:schmidt@naa.net \X/