or just one thing if you please explain these commands. i think my confusion will be cleared mdadm --assemble /dev/md1 /dev/hda1 mdadm --assemble /dev/md3 /dev/hda3
mdadm --add /dev/md1 /dev/hdb1 mdadm --add /dev/md3 /dev/hdb3 what is the difference in both command thanks. any help will be highly appreciated. On Wed, Jul 18, 2012 at 12:36 AM, Muhammad Yousuf Khan <sir...@gmail.com> wrote: > On Mon, Jul 16, 2012 at 6:39 PM, Gary Dale <garyd...@rogers.com> wrote: >> On 16/07/12 08:12 AM, Muhammad Yousuf Khan wrote: >>> >>> apart from my question i know what does "assemble" mean but most of >>> the time it create conflict with the option "add". >>> for example. >>> >>> if raid is broken then i can just re-add the the broken partition >>> >>> if my HD fails then i will add the new drive, recreate the partition >>> and add it to new array and cat /proc/mdstat will show me the sync >>> status. >>> >>> but now the next question coming in my mind is why assemble. >>> >>> i also observed that some time when i restart the computer contain >>> RAID1 after 2 or 3 months it start to test or (maybe)assemble one of >>> the partition by saying that (more or less) that the raid has not been >>> tested for this this days so now reassembling (sorry if i am wrong >>> since i can not recall the whole message) >>> so the point why assemble is necessary? >>> >>> if assembling is that necessary then why should i wait to restart. i >>> can do this manually every week or can schedule a task for it. >>> >>> Thanks, >> >> Assemble builds the arrays based on the information contained in the >> superblock. The testing you are talking about is more likely fsck checking >> the file system(s) on the arrays. > > if Assemble builds the array then what is the purpose of "--create" > option. sorry if my question is a bit annoying but i am confuse in > this. > > is there a difference in creating and building the array? > > Thanks, > >> >> It is possible for arrays to get out of sync due to a power outage or >> improper shutdown but in practice this is unlikely. Nonetheless, mdadm >> should also check for the consistency of the arrays periodically. If it >> doesn't do this and a drive fails, it may not be possible to rebuild the >> array. >> >> The /etc/crontab.d folder on my Wheezy system contains an mdadm entry which >> was put there by the package maintainer or developer. It includes the line: >> >> 57 0 * * 0 root if [ -x /usr/share/mdadm/checkarray ] && [ $(date +\%d) -le >> 7 ]; then /usr/share/mdadm/checkarray --cron --all --idle --quiet; fi >> >> which checks all the arrays once a month. This is a trade off since you >> don't want to spend too much time checking arrays. If possible, you may want >> to run checkarray before your drive has failed to ensure that your array is >> consistent before pulling the failing drive. >> >> >> -- >> To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject >> of "unsubscribe". Trouble? Contact listmas...@lists.debian.org >> Archive: http://lists.debian.org/50041992.7020...@rogers.com >> -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/cagwvfmmhtdfr04zjjig+jxnpahqsbpt844cb-kgyw0_1mqf...@mail.gmail.com