Windows / Linux Partition Confusion!

Hello All!

I recently decided to give Linux OpenSUSE 11.0 a try, by dual booting it with my xp machine.

I am pretty fluent with Windows, and know my way around very well, but I am very new with the Linux File system, and how the Linux Partitions are set up.

I decided to do a clean install of XP, followed by a clean install of OpenSUSE 11.

My original objective was to give the windows partition the majority of my hard drive, since I play alot of games, and will have more data needed for xp. It is a 250GB WD sata hard drive, I planned on giving xp roughly 70% of the space on the drive, and rest to linux.

While this was very easy to figure out in Ubuntu (Just move the little partition slider, and it set everything up for you) It was a little more complicated with OS 11.0, and I was a little scared to mess with the partition setup, so I just let it partition based on installation defaults.

So what it did was end up splitting my hard drive up into SIX partitions? That’s what linux shows under the partition tool inside the operating system, but windows shows only 5 partitions. Here is a screenshot showing what I have explained.

Can someone please help me understand why there are so many partitions for linux, and what each partition was created for? Are any of those listed partitions “Empty” that I could assign a drive letter to, and use for storage inside of windows? It left me with about 90GB’s for windows, when I actually was hoping to get about 200GB’s for windows, and the rest for Linux.

Any help, or explanation is greatly appreciated! Sorry If used incorrect terminology, I am still very new to the Linux environment.


Both systems are seeing the same number of partitions.

The little difference is that Linux includes also in the list the extended one, which is not a real partition but a container.
Keep in mind that in a (dos partition compliant) disk drive only 4 primary partitions can be created in the partition table.
To circumvent such limitation, the concept of extended partition was introduced.

Appart from that, everything seems to be OK.

Find more details about disk and partitions in the following url
SDB:Partitioning for SuSE Linux - openSUSE


Usually the install sets up partitions for “/” which contains the OS files “/home” for your documents and personal settings and “swap” for the swap file. Perhaps someone can help about sda5 partition you have. I see from the screenshot that openSUSE has not got it mounted. You didn’t still have Ubuntu installed?

Also note that during the install process you can enter the expert partitioner (based on current proposal option) and resize the partitions with the slider.

First, as @carboncore explained, Windows is showing six partitions. The green line rectangle with individual partitions within having blue top lines, that’s how Windows displays an extended partition. It is a visual container.

The reason for the additional partitions: Usually in the simplest desktop linux setup, there are three. One is for the OS itself, in linux called “root” but designated with a forward-slash ("/") as the mount point. Roughly equiv to the Windows C root directory plus the Windows directory. The second is /home, roughly equiv to Windows Documents and Settings; where all the user specific config files are, and just like with Windows, you can put user data there, too (although, again just like with Windows, many users create separate partitions for that). The third is the swap partition for virtual memory, the equiv of Windows pagefile.

The reason an extended was created is that four partitions were asked for (I’ll come back to this below; important). Even with just the basic three above, that would have taken all of the remaining partition table slots preventing adding any more partitions without deleting one of the three. So this was the correct method to use.

Now, look carefully at the partition sequence in Windows and in openSUSE, the sizes, and in the openSUSE image the start/end cylinders. The Windows diagram is showing the partitions in the order they physically reside on the disk. The openSUSE image is listing the partitions as they are in the disk partition table (in Windows the listing above the picture is probably this way, too). What has happened is that the partition numbers are not sequential; this occurs when partitions are moved or resized or inserted or created in more than one pass or . . . there are a number of ways it can happen. In any event, the actual physical sequence on the disk following your Windows C partition, is sda3, sda6, sda7, and sda5.

In Windows, think of it as having unallocated space which you arbitrarily assign a volume letter to (Windows allows you to use any unassigned letter); your physical disk layout does not match the alpha sequence. And you may not care, either in Windows or in linux. It’s not as clean and simple as sequential; you just need to remember which is which (and once that’s done in linux, using the mount points, it will be easier than remembering drive letters in Windows). In Windows, drive letters are assigned and stored in the registry, and then written to the disk signature of the partition in the table; that’s how Windows knows which partition “C” is (and why changing a drive letter can be a nightmare). In linux, it is the partition number in the table, period. And while in Windows, C, D, E, etc. are called “drives”, they of course are not (the proper MS term is actually “volume”); in linux, they are, well, partitions.

Finally, for more space. You have at least 70GB unused; sda5 does not have a mount point. It was formatted with ext3, but if you wish to reclaim that for Windows and reformat it with NTFS, you can do so. I would do that straightaway, because it is possible that Windows may corrupt the partition table in the process. This is way too long to explain here, but Windows doesn’t play nice in the table with anything other than itself. Fortunately, it’s physically at the end of the disk and the last logical within the extended chain, which reduces the risk of something else being affected. But have a backup of C just in case of Murphy’s Law. So that is 70GB. /home was sized at 50GB. Now, in theory if you wished this could be reduced and the freed space used for another partition, but because it is the 2nd primary and in the middle and an additional partition would have to be a logical - well, the table would really look screwy and there would be much more risk in making those physical changes. You could of course blow all this away and reinstall, partitioning precisely as you wish.

Wow thanks for the quick replies! It all makes so much more sense now.

I will go ahead and delete and reformat the 70GB, sda5 partition using NTFS, and let you all know how it goes. I am only a day into the Windows / Linux reinstall, so if something goes hay wire, worst case scenario would be to just reformat and start all over, which isn’t bad because I just did it last night and there still isn’t much on the machine. I just hope all this doesn’t adversely affect the performance of my fresh install! If it does, oh well, more practice for me!

Thanks everyone! This is an awesome community! Now I know why everyone praises the OpenSUSE community so much.

Naw . . . it’s mostly because so many of us are old. :slight_smile: