A: As of 18 Sept 1997, it is "2.0.30 + pre-9 2.0.31 + Werner Fink's swapping patch + the alpha RAID patch". As of November 1997, it is 2.0.31 + ... !?
A: Make sure that/usr/include/linuxis a symbolic link to/usr/src/linux/include/linux. Make sure that the new filesraid5.c, etc. have been copied to their correct locations. Sometimes the patch command will not create new files. Try the-fflag onpatch.
A: raidtools-0.42 requires linuxthreads-0.6 from: ftp://ftp.inria.fr/INRIA/Projects/cristal/Xavier.Leroy Alternately, use glibc v2.0.
mdrun -a /dev/md0: Invalid argument
A: Usemkraidto initialize the RAID set prior to the first use.mkraidensures that the RAID array is initially in a consistent state by erasing the RAID partitions. In addition,mkraidwill create the RAID superblocks.
mdrun -a /dev/md0: Invalid argument The setup was:
cat /proc/mdstat shows
Personalities :
read_ahead not set
md0 : inactive sda1 sdb1 6313482 blocks
md1 : inactive
md2 : inactive
md3 : inactive
mdrun -a generates the error message /dev/md0: Invalid argumentA: Trylsmod(or, alternately,cat /proc/modules) to see if the raid modules are loaded. If they are not, you can load them explicitly with themodprobe raid1ormodprobe raid5command. Alternately, if you are using the autoloader, and expectedkerneldto load them and it didn't this is probably because your loader is missing the info to load the modules. Edit/etc/conf.modulesand add the following lines:alias md-personality-3 raid1 alias md-personality-4 raid5
mdadd -a I get the error: /dev/md0: No such file or directory. Indeed, there seems to be no /dev/md0 anywhere. Now what do I do?
A: The raid-tools package will create these devices when you runmake installas root. Alternately, you can do the following:cd /dev ./MAKEDEV md
/dev/md0, I try to mount it and get the following error: mount: wrong fs type, bad option, bad superblock on /dev/md0, or too many mounted file systems. What's wrong?
A: You need to create a file system on/dev/md0before you can mount it. Usemke2fs.
On my Linux 2.0.30 system, while doing amkraidfor a RAID-1 device, during the clearing of the two individual partitions, I got"Cannot allocate free page"errors appearing on the console, and"Unable to handle kernel paging request at virtual address ..."errors in the system log. At this time, the system became quite unusable, but it appears to recover after a while. The operation appears to have completed with no other errors, and I am successfully using my RAID-1 device. The errors are disconcerting though. Any ideas?
A: This was a well-known bug in the 2.0.30 kernels. It is fixed in the 2.0.31 kernel; alternately, fall back to 2.0.29.
mdrun a RAID-1, RAID-4 or RAID-5 device. If I try to mdrun a mdadd'ed device I get the message ''invalid raid superblock magic''.
A: Make sure that you've run the mkraid part of the install procedure.
/dev/md0, the kernel spits out a lot of errors like md0: device not running, giving up ! and I/O error.... I've successfully added my devices to the virtual device.
A: To be usable, the device must be running. Use mdrun -px /dev/md0 where x is l for linear, 0 for RAID-0 or 1 for RAID-1, etc.
cat /proc/mdstat shows the total size of the device, but df only shows the size of the first physical device.
A: You must mkfs your new md-dev before using it the first time, so that the filesystem will cover the whole device.
/etc/mdtab using mdcreate, I've mdadd'ed, mdrun and fsck'ed my two /dev/mdX partitions. Everything looks okay before a reboot. As soon as I reboot, I get an fsck error on both partitions: fsck.ext2: Attempt to read block from filesystem resulted in short read while trying too open /dev/md0. Why?! How do I fix it?!
A: During the boot process, the RAID partitions must be started before they can befsck'ed. This must be done in one of the boot scripts. For some distributions,fsckis called from/etc/rc.d/rc.S, for others, it is called from/etc/rc.d/rc.sysinit. Change this file tomdadd -ar*before*fsck -Ais executed. Better yet, it is suggested thatckraidbe run ifmdaddreturns with an error. How do do this is discussed in greater detail in question 14 of the section ''Error Recovery''.
invalid raid superblock magic while trying to run an array which consists of partitions which are bigger than 4GB.
A: This bug is now fixed. (September 97) Make sure you have the latest raid code.
Warning: could not write 8 blocks in inode table starting at 2097175 while trying to run mke2fs on a partition which is larger than 2GB.
A: This seems to be a problem withmke2fs(November 97). A temporary work-around is to get the mke2fs code, and add#undef HAVE_LLSEEKtoe2fsprogs-1.10/lib/ext2fs/llseek.cjust before the first#ifdef HAVE_LLSEEKand recompile mke2fs.
ckraid currently isn't able to read /etc/mdtab
A: The RAID0/linear configuration file format used in/etc/mdtabis obsolete, although it will be supported for a while more. The current, up-to-date config files are currently named/etc/raid1.conf, etc.
raid1.o) are not loaded automatically; they have to be manually modprobe'd before mdrun. How can this be fixed?
A: To autoload the modules, we can add the following to/etc/conf.modules:alias md-personality-3 raid1 alias md-personality-4 raid5
mdadd'ed 13 devices, and now I'm trying to mdrun -p5 /dev/md0 and get the message: /dev/md0: Invalid argument
A: The default configuration for software RAID is 8 real devices. Editlinux/md.h, change#define MAX_REAL=8to a larger number, and rebuild the kernel.
md work with partitions on our latest SPARCstation 5. I suspect that this has something to do with disk-labels.
A: Sun disk-labels sit in the first 1K of a partition. For RAID-1, the Sun disk-label is not an issue since ext2fs will skip the label on every mirror. For other raid levels (0, linear and 4/5), this appears to be a problem; it has not yet (Dec 97) been addressed.