What is the reason of /boot and /tmp partitions in Ubuntu ?

  • Please clarify your question... – hexafraction May 4 '12 at 15:47
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    Nothing goes wrong if you do not have a /boot partition :) – Rinzwind May 5 '12 at 7:13
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    /boot does not bother much. Even only giving swap areas(even not required today for better systems) and assigning only the root( / ) partition would get me my linux running. They why is it required to mention such long list of partitons? – ashutosh May 5 '12 at 7:18
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    You keep posting the same question. You need to follow the default partitioning setup, or read the official documentation on partitioning. Posting the same question over and over isn't a good idea. – Tom Brossman May 5 '12 at 8:02
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    @siraj - I have merge all your identical questions into this one. Please do not post similar questions. The way we work is constantly editing your question with any further information until you have an answer that you can accept (clicking this tick button next to the answer). Thanks! – fossfreedom May 5 '12 at 9:11

There isn't any technical problem with not assigning a separate /boot partition. The following link may help you to understand why making an external boot partition is preferable. But as they say, it is only preferred, not NECESSARY to allocate a separate boot partition. I myself have used only the / (root) and swap area to partition my drive and I've installed Ubuntu without any issues. https://help.ubuntu.com/community/CreateBootPartitionAfterInstall

  • make it an answer if it does :) – ashutosh May 5 '12 at 7:44
  • Its upto Siraj to make it an answer as he is the one who asked the question. – harisibrahimkv May 5 '12 at 7:45
  • yeah, a hint for him ;) – ashutosh May 5 '12 at 7:46

Please take a terminal and type in "man hier". :)

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    +1, nice hint. Granted, not what the OP asked, but still, man hier is useful knowledge, and the question was poorly written anyway – MestreLion May 4 '12 at 16:02

I think perhaps there is a misunderstanding as to what partitioning does.

If you let the Ubuntu installer do the partitioning there will only be two partitions

~19 GB for '/'
~ 1 GB for swap

So what happened to /boot, /home, and /tmp?? Doesn't Ubuntu need those to function correctly?

Yes, it does. But it does not need them as partitions. It needs folders (aka "directories") with those names. And in the standard Ubuntu install, the filesystem in the partition for '/' will have directories with those names. So everything will function correctly.

If there is nothing on the hard disk when you install Ubuntu, then a few windows into the install you will get a window like the image below asking what type of an install you want to do.

My advice is that unless you have a some specific reason to split your installation into separate partitions, do not do it. Just use the entry which is selected in the example. Having one root ('/') partition which contains all of your data is usually the most efficient way to use the space on a hard drive.

enter image description here


Mounting /boot on another partition is useful if your root partition uses a file system that grub2 (the bootloader) cannot understand ; you can place enough components in /boot to mount the root file system. This is not the case in a typical Ubuntu installation, as grub2 understands the default recommended file system (ext4), and all the other choices available. Another situation where a separate /boot is useful is where you have particularly stringent security needs - you can avoid mounting the /boot partition unless you need to update the components within, which means that rootkits will find it harder to compromise the bootloader. Again, this is not a typical need and is a rare choice.

/tmp on a separate partition is useful if you have applications that need to heavily use temporary files and you would like to use a block device that is very fast. Alternately, if you are booting from an SSD, and would like to reduce the amount of wear on your SSD, you can mount /tmp on another drive, or in RAM. Again, this is an uncommon configuration.

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    mounting /tmp is not that uncommon... it is actually a very nice thing to do even if you don't have an SSD. I set up mine once in /etc/fstab, capped at 4GB (but it only uses what it needs, so very little actual RAM is allocated), and lived happy everafter – MestreLion May 4 '12 at 16:00
  • I've upvoted this for adding in the technical reasoning, even though I don't necessarily agree (as @MestreLion indicates) that mounting /tmp really is uncommon. Perhaps uncommon for default desktop Ubuntu installations, but I'd agree that it's been quite common historically for Linux/Unix. – belacqua Aug 8 '12 at 23:04

Yeah, use the entire disk if you don't understand the whole partitioning thing. Besides, it is silly to separate the disk by limited sizes; when it get fulls then you have to increase size.... Just go with the full disk unless you have a special technical need for making separate partitions....


The only problem I see is

/tmp  5 Gb
/boot 5 Gb

Why? Both are not needed. /tmp is a temporary directory so it is not likely to hold alot of files. And those files tend to get deleted fairly quickly aswell. So I would discard that one. Same goes for boot. When you have more than 1 OS and want to save space you can share /boot with all those OSes but there is not really a need for it. It can be handy but in this case I would go without and focus on the low disc space.

My root at this moment is 5.9 Gb large so I would increase / a bit so you do not run into a disc full notice.

/ = 10 GB 
swap = 2 GB  
/home = 8 GB (my files music, videos etc are saved in my pen drive or cd)

sounds better to me.

If you use your pen drive for storage I would even suggest you should focus on the low disc space and even forget about a /home partition:

swap 2 Gb
remainder as /
  • What happend doing partition whitout /boot – siraj May 5 '12 at 7:15
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    nothing! Most people do not bother with a /boot partition. I added in some more details. – Rinzwind May 5 '12 at 7:19
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    Nothing goes wrong if you do not mention /boot. Just mention the root partions. It is for programming purpose, that temp partiition is sometime required to be mentioned externally, but ONLY ROOT PARTITION MATTERS – ashutosh May 5 '12 at 7:19

Well, there are many guides out there for the partitioning in ubuntu, I would prefer to partiton it in this way:
First, Just follow this link and let me know if you are getting stuck to any point out there. Now I also want to know wether or not you are doing the partition in a preinstalled windows hard disk or a fresj installation over entire disk?

EDIT: Well, I would first recommend you to use gparted to create and manage partition. Just create four 5 gb primary partitions and format it with ext4 file system in it. Then just create a extended file system on one of the four primary partition because they won't allow you to create more than 4 primary partitions on the disk. Now on the extended one, create a 3 gb and a 2 gb logical paritions. Now you just got the partitions in the following way:

partition 1    size: 5 Gb   type: Primary
Partition 2    size: 5 Gb   type: Primary
Partition 3    size: 5 Gb   type: Primary
Partition 4    size: 5 Gb   type: Extended
**Partition 4** -->  
     Partition 5     SIZE: 3 GB    Logical
     Partition 6     SIZE: 2 Gb    Logical

Now just format and assign each of the partition as their respective choice and use it in either way you want. Linux gives you the better way to do it threw Gparted.

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    No reason really to have this as a second answer -- why not combine? – belacqua Aug 8 '12 at 23:06

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