Red Hat Bugzilla – Bug 9069
RH6.1 installation corrupting partition table
Last modified: 2008-05-01 11:37:54 EDT
After unsuccessfully attempting to install RH6.1 into a logical partition in the extended partition, Partition Magic refuses to run because Disk Druid altered the Logical Partition's linked list so that the partitions have different physical and logical orders (error 120). Scenario: 14 gigabyte hard drive with 2 primary partitions (one 3gb fat32 with current installation of Win98, one 700mb fat16 with installation of Win98 from previous motherboard left hidden in semi-perpetuity until I have time to satisfy myself that I'll never need anything off of it again), and an extended partition with 3 logical partitions and 2gb free space at the beginning into which I intended to create two more logical partitions: the ext2 partition for Linux and the swapfile partition. I created the swapfile first (I think Disk Druid assigned it /hda9), then created the ext2 partition (I think Disk Druid then re-named the swapfile /hda10 and named the ext2 partition /hda9). Why that order? So I could assign the swapfile 128mb (bumped up to 133 by Disk Druid, probably just a 1024 vs 1000 nomenclature difference), then assign the remainder of the free space to the ext2 partition (actually I told DD to make it 1mb and grow to fill the remaining space). During the first attempt, Disk Druid seemed to run OK, but a fatal error occurred during the format attempt. I restarted and tried again, and the same thing happened. For the third attempt, I tried booting and installing from the RH6.0 CD on the theory that I might have just burned a bad copy from the 6.1 ISO file. This time, it made it past the formatting stage, but reported that I didn't have enough space to install the files I'd selected. The amount of space needed seemed to be approximately the same amount of space as the files I'd selected, implying that the available free space on the new ext2 partition was somewhere around 0-1 megabytes. At that point, I called a friend who uses Linux as his primary OS. His theory was that I was probably straddling or beyond the 1024 cylinder limit. At that point, I booted back into Windows & ran Partition Magic 4 in an effort to clean up the mess, delete the two new partitions, and shuffle things around a bit to make room at the beginning of the disk for Linux. PM refused to touch the disk because of an error 120. Apparently, it was unhappy because the logical partitions weren't linked in physical order, i.e., logical partition #4 (swapfile) began at a lower cylinder than logical partitions 1, 2, and 3 (all fat32); partition #5 (ext2) began at a lower cylinder than #4 (swapfile). This particular bug doesn't even touch upon the more serious issue of why the installer wasn't able to continue with the installation (perhaps because the partition was beyond the 1024-cylinder limit & neither disk druid nor installer provided any warning that Bad Things would happen if the installation continued). However, the search I did on DejaNews (for "Disk Druid" & 120) turned up enough similar experiences from others who were unable to run Partition Magic (or FDISK) after using Disk Druid to show that this particular bug isn't particularly rare. While it's not immediately fatal (Windows still runs fine), it's going to cause a lot of inconvenience because apparently the only way to get rid of the error 120 once and for all is to back up everything, wipe the entire hard drive, and restore everything.
There are two issues here - I will address the Partition magic related issue first. Disk druid follows the behavior of the linux fdisk program when it allocates new logical partitions - I know partition magic advertises that it now works with Linux so I would think they would have tested it against fdisk. Perhaps there is an updated version of Partition Magic that might fix this issue... The second issue is why the installer fails with your original attempt. What is the fatal error you get when the installer fails?
I think part of the problem might have been that the extended partition was type f instead of type 5. After I backed up, wiped, and restored the hard drive, I created the ext2 and swapfile partitions using partition magic as the first two logical partitions within the extended partition. This time, I made sure I only used disk druid to set the mount point. The installation seemed to complete, but for some reason networking never got installed (in particular, ifconfig and ifup were both nowhere to be found). When I tried to re-run the RH6.1 installer and perform an upgrade, it told me that there was no Linux installation to upgrade. A few more trips to the RH knowledge base later & armed with the knowledge that the original RH6.1 installer got confused by extended partitions of type f, I tried using the Anaconda boot disk and update disk. No luck; it still didn't see the Linux installation. At that point I was mad enough to throw caution to the wind and use fdisk to temporarily change the partition type of the extended partition from type f to type 5 & tried again. This time, the upgrade attempt worked. It installed about 49 RPMS totaling 128mb (presumably that it skipped installing the first time around, since I didn't actually tell it to install anything new), and the result was a working installation. Just to be safe & keep Windows happy, I ran fdisk again and changed the extended partition back to type f. So far, it's still working. Suggestion to pass on for future consideration: define a URL on your site (readmefirst.redhat.com, maybe?) that will always contain a brief summary of current installation issues with the most recent CD (especially issues those that are new to the current release and those that can result in a failed installation or hard drive corruption, even if the person doing the installation has installed Linux dozens of times before in the past and wouldn't be expecting anything unusual to come up and bite him this time around), as well as patches and updates likely to be of immediate interest to someone who wants to install RH Linux _RIGHT NOW_, but could be persuaded to download a few files first and endure creating a few floppies if somebody tells him it's really important to do so instead of just booting from the CD.