What is the recommended size for a Linux /boot partition?
Solution 1:
These days, 100 Megabytes or 200 Megabytes is the norm.
You do not need to have a /boot partition. However, it's good to have for flexibility reasons (LVM, encryption, BIOS limitations).
Edit:
The recommended size has been increased to 300MB-500MB.
Also see: https://superuser.com/questions/66015/installing-ubuntu-do-i-really-need-a-boot-parition
Solution 2:
I tend to create a 1 GB /boot. I leave a live CD image which has various repair tools in my /boot. I mostly do this for systems that at the remote sites I support.
With the right configuration, and enough memory, GRUB 2 can boot the image without extracting the contents. A couple of times I have talked remote staff into rebooting the system to the live CD image and starting networking/ssh on a system that was having issues so I could connect and repair things.
This certainly isn't required, or even common.
Solution 3:
What is the recommended size for a Linux
/bootpartition?
The /boot partition contains the GRUB configuration, the kernel with their System.map, ... I think ~ 100 MB is enough.
And is it safe to not have a
/bootpartition?
Yes. But a separate /boot partition has some advantages:
- As a rescue partition
- rootfs is on a LVM, RAID, is encrypted, or unsupported by GRUB
- Maybe saves a few seconds of the boot time
Solution 4:
It also differs distribution from distribution. For example for Fedora minimum is 250 MB[1] and 500 MB is default and if you plan to (pre)upgrade in the future 500 MB is required[2]. If space is not a problem I would go for 1 GB to prevent shuffling partitions later as I had to do when upgrading recently.
[1] http://docs.fedoraproject.org/en-US/Fedora/16/html/Installation_Guide/s2-diskpartrecommend-x86.html
[2] http://fedoraproject.org/wiki/How_to_use_PreUpgrade#Not_enough_space_in_.2Fboot
Solution 5:
As we have seen quite an increase in linux kernel storage requirements and ever increasing initrds, I nowadays (February 2018) tend to allocate 1 GB of storage for /boot.
As /boot is usually the only thing that is not on LVM, it is the only partition you cannot resize easily. Thus "wasting" a few hundred megabytes usually doesn't hurt as bad as a /boot filesystem that turns out to be too small in maybe 5 or 10 years.