hi gavin, thanks for your feedback which is great as always !!!
I have currently two sata disks as indicated one with the system (250GB Samsung) and one with home (500GB Samsung). on the home drive there is about 2GB of data, so I can put that on a dvd. the system drive has edubuntu 7.10 and I will upgrade to 8.04 anyway by reinstalling from scratch. we haven't really installed a lot of programs. basically just java, mysql some codecs and some games. I can install all this quite quickly from the repository. thanks for your words on the installation of raid. they will be very useful. as I am doing the LPI right now (6 of 9 month done) I have already setup raid during the course and I also have some documentation, which will get me going. is there anything that I should not put on the raid or is not worth it, like eg. swap? I will probably put system and home on one drive and have another disk for the raid because 500 GB are really enough for our purposes. and I can use the thrid disk for downloads or setting up a mirror of a repository (which I did in the past). I think about it over the weekend. thanks again, uwe Zitat von Gavin McCullagh <[EMAIL PROTECTED]>: > Hi, > > On Thu, 31 Jul 2008, Uwe Geercken wrote: > >> at the time I setup the system, I have used one harddisk for the >> system and one for the home directories of the students. so these are >> on seperate drives. > > What sizes are the respective drives? Are they IDE, SATA, SCSI? > >> I am now thinking putting in a second drive and use software raid so >> that I will have faster reads. my first thought was to use raid for >> the system and still have the home folders on a seperate drive. or >> maybe I should put home and the system on the same drive and use raid >> for both? > > I presume you're talking about MD (linux kernel software raid). Presumably > it can read off the disks independently so you should probably get improved > read speeds. To my mind though, reliability is the best feature of RAID1. > > http://en.wikipedia.org/wiki/Standard_RAID_levels#RAID_1_performance > > If you can get both the system and the home directories onto RAID1, you're > system will keep running in the event of a single disk failure. Disk > failure is remarkably common these days. > > Migrating the running system to software RAID is not easy, so you may find > it easiest to reinstall which is a bit of a downside. Presumably you can > just back up and restore the home directories with tar. For the system, if > you have sufficient space and don't wish to reinstall, you could possibly > do something like > > 1. Shrink your / partition by 50% using gnu parted > 2. Create a new equal sized partition in the resulting space. Make it of > type linux-raid > 3. Create a larger raid partition on the new disk. > 4. Use mdadm to create a raid1 array using the two raid partitions. > 5. Format the raid partition ext3 (or whatever you're using) > 6. Reboot and make sure the raid partition comes back up. > 7. Drop to single user mode and use something like cpio or rsync to sync > the new raid partition with the old one. > 8. Configure grub with extra boot items to boot onto the new partition > 9. Reboot using the new grub entry and say a prayer (if it doesn't work, > you should be able to boot onto the old partition anyway). > 10.Once you're up on the new partition, you can re-run grub-install, > delete the old non-raid partition, expand the existing one back into the > freed space, expand the raid array into the space and finally expand the > root filesystem on the bigger partition. > > These instructions are untested and I've probably missed something. > Frankly, I'd highly recommend the reinstall, backing up your config first > of course! > > Gavin > > > -- > edubuntu-users mailing list > [email protected] > Modify settings or unsubscribe at: > https://lists.ubuntu.com/mailman/listinfo/edubuntu-users > -- edubuntu-users mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/edubuntu-users
