Rock on, Mike. Gratz on finding your way through that, and getting it working. I enjoyed reading your summary. :) -Rob On Thu, May 3, 2012 at 4:56 PM, Mike Miller <mbmiller+l at gmail.com> wrote: > Thanks for all of the helpful suggestions. A guy usually known as gkey > (or "gk") was most helpful. The crazy thing about my problem was that it > wasn't all that difficult or tricky and most of the info on the web was > steering me into all kinds of unneeded complexities. It turned out that > these were the issues: > > (1) disks of more than 2TB have different requirements than disks of 2TB > or less -- we can't use the usual DOS partitioning and fdisk with the > bigger disks, so we have to use GPT partitioning and gdisk instead > > (2) When using GPT partitions we can't add /boot to the RAID1, and /boot > has to have partition type "BIOS boot partition". > > (3) I was also told to leave 10MB empty at the beginning of both drives. I > didn't test that those 10MB were actually needed, but I did leave that > space and everything worked, so I'm inclined to believe the gkey's claim > that it is necessary. > > > If you are trying to do this, I hope you won't be intimidated by the > instructions below. They aren't as long as they seem because most of it is > output, not input. It's pretty straightforward. > > > When installing Ubuntu 12.04 on the 3TB RAID1, it helps a lot to have > cgdisk and gdisk handy, but they are not on the Live CD and they are not > available via apt-get. That's an annoyance Ubuntu should fix. I had to > compile them on another machine. I then used scp to copy them over after > booting to Live CD. One trick was that I had to compile gdisk and cgdisk, > but I only had an older Ubuntu box to compile it on. When I copied the > compiled binary for cgdisk to the running Ubuntu 12.04 Live CD, it didn't > work because it was looking for older versions of various /usr/lib/libicu* > files. I had to edit the Makefile to fix that, which is a lot easier than > you would think, especially given that they had instructions on how to fix > this problem in the README file. To make this easier for you, if you need > to do this work, I put the two binaries here: > > http://genetsim.org/gdisk/ > > ...and you can download both of them and make them executable using this > pair of commands: > > wget http://genetsim.org/gdisk/{c,}**gdisk<http://genetsim.org/gdisk/%7Bc,%7Dgdisk> > chmod 755 {c,}gdisk > > The UTF support is turned off, so if you want to use special UTF > characters in formatting your disks, this may not be for you. If you want > to know exactly what I did to make them work on Ubuntu, here's the info: I > was using gdisk_0.8.1.orig.tar.gz. The Makefile diff of changes is below > (if you are not familiar, all this tells you is that any line shown below > beginning with "<" was changed into the subsequent line beginning with > ">"). Basically, I removed "-D USE_UTF16" and any option beginning with > "-licu". > > $ diff Makefile_original Makefile > 4c4 > < CXXFLAGS+=-Wall -D_FILE_OFFSET_BITS=64 -D USE_UTF16 > --- > >> CXXFLAGS+=-Wall -D_FILE_OFFSET_BITS=64 >> > 18c18 > < $(CXX) $(LIB_OBJS) gdisk.o gpttext.o $(LDFLAGS) -licuio -licuuc > -luuid -o gdisk > --- > >> $(CXX) $(LIB_OBJS) gdisk.o gpttext.o $(LDFLAGS) -luuid -o gdisk >> > 22c22 > < $(CXX) $(LIB_OBJS) cgdisk.o gptcurses.o $(LDFLAGS) -licuio -licuuc > -luuid -lncurses -o cgdisk > --- > >> $(CXX) $(LIB_OBJS) cgdisk.o gptcurses.o $(LDFLAGS) -luuid -lncurses >> -o cgdisk >> > 26c26 > < $(CXX) $(LIB_OBJS) sgdisk.o gptcl.o $(LDFLAGS) -licuio -licuuc > -luuid -lpopt -o sgdisk > --- > >> $(CXX) $(LIB_OBJS) sgdisk.o gptcl.o $(LDFLAGS) -luuid -lpopt -o >> sgdisk >> > > > The other thing you'll need to install is mdadm, for setting up the RAID1. > That's a lot easier to get, if you have network connectivity: > > sudo apt-get install mdadm > this installs postfix, choose "local" installation, and default name > > > Now use cgdisk, e.g.,... > > sudo cgdisk /dev/sda > > ...which I think is the easiest option, to set up the partitions. You > want to use blocks of a certain size so that you get proper alignment. > Don't just make up numbers, actually multiply things out. It wants you to > supply a certain number of 512-byte blocks. My HDD uses larger blocks, I > think 2048-byte, but I did everything in terms of sets of 2048 512-byte > blocks (mebibytes or MiBs). In other words, in cgdisk, a mebibyte (MiB: > 1,048,576 bytes, formerly known as a megabyte) is 2048 and 10 MiB is 20480 > because that's the number of 512-byte blocks you'll be using. > > In my simple case, I just wanted to leave 10 MiB free at the beginning, > then have a 200 MiB /boot, a 32 GiB swap and the rest as /, but leaving > about 100 MiB free at the end. To do that I used these numbers of 512 byte > blocks... > > start at 20480 add 409600 > start at default add 67108864 > start at default add 5792787343 > > ...and these were the sizes, types and names of my partitions: > > Part. # Size Partition Type Partition Name > ------------------------------**------------------------------**---- > 10.0 MiB free space > 1 200.0 MiB BIOS boot partition /boot > 2 32.0 GiB Linux RAID swap > 3 2.7 TiB Linux RAID / > 101.0 MiB free space > > Probably you will be like me and your first disk will be /dev/sda and the > second will be /dev/sdb. I ran cgdisk to get what you see above on > /dev/sda then ran exactly the same numbers on /dev/sdb. > > After running cgdisk, including writing the partitions (essential) and > quitting, I checked what I had in gdisk as follows: > > $ sudo ./gdisk -l /dev/sda > GPT fdisk (gdisk) version 0.8.1 > > Partition table scan: > MBR: protective > BSD: not present > APM: not present > GPT: present > > Found valid GPT with protective MBR; using GPT. > Disk /dev/sda: 5860533168 sectors, 2.7 TiB > Logical sector size: 512 bytes > Disk identifier (GUID): 73650704-727A-4863-B31D-**997F8201656C > Partition table holds up to 128 entries > First usable sector is 34, last usable sector is 5860533134 > Partitions will be aligned on 2048-sector boundaries > Total free space is 227294 sectors (111.0 MiB) > > Number Start (sector) End (sector) Size Code Name > 1 20480 430079 200.0 MiB EF02 /boot > 2 430080 67538943 32.0 GiB FD00 swap > 3 67538944 5860326286 2.7 TiB FD00 / > > The result is identical for /dev/sdb, except for GUID: > Disk identifier (GUID): 60C3D922-19EC-4A14-8D6B-**6F932CDC9D9C > > Once you have the partitions, you can run mdadm to create the RAID1. For > me that went like this (first swap, then /): > > sudo mdadm --create /dev/md0 --level 1 --raid-devices 2 /dev/sda2 > /dev/sdb2 --metadata=1.2 > sudo mdadm --create /dev/md1 --level 1 --raid-devices 2 /dev/sda3 > /dev/sdb3 --metadata=1.2 > > Note that I did not add /boot to the RAID -- that will cause Ubuntu to > fail to load GRUB, so don't do that. > > Next I set up the swap on the new swap partition on the RAID1: > > $ sudo mkswap /dev/md0 > mkswap: /dev/md0: warning: don't erase bootbits sectors > on whole disk. Use -f to force. > Setting up swapspace version 1, size = 33553332 KiB > no label, UUID=559c4534-1d13-47d0-af72-**e802d3d7f944 > > > Now leave the Live CD and boot with the Alternate CD. You need the > Alternate CD to install Ubuntu on the RAID. When you get to the screen > where it asks you to partition your disks, the swap should be all set. Make > sure to identify the RAID partition you will use for / and tell Ubuntu that > / goes there and what format to use (e.g., ext4) -- setting up / is done > only in the RAID, not in the /dev/sda or /dev/sdb. You might also check > that both of the /boot partitions on /dev/sda and /dev/sdb are set up > properly -- both called /boot and both using the "BIOS boot partition" type. > > When you get the question about whether to install GRUB on both disks or > just one of them (it says something about what happens whether you want to > boot with a degraded drive) -- I chose both so that I will be able to boot > with a degraded drive and see what's going on with it. I'm not always in > the office and if it is running I can see it remotely. > > When Ubuntu installed GRUB, it then installed it on both /dev/sda and > /dev/sdb. I rebooted, everything looked great. > > Thanks, everybody! (esp., gkey). > > Mike > ______________________________**_________________ > TCLUG Mailing List - Minneapolis/St. Paul, Minnesota > tclug-list at mn-linux.org > http://mailman.mn-linux.org/**mailman/listinfo/tclug-list<http://mailman.mn-linux.org/mailman/listinfo/tclug-list> > -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://mailman.mn-linux.org/pipermail/tclug-list/attachments/20120503/0aaa004c/attachment-0001.html>