What is the recommended size for a Linux /boot partition?

What is the recommended size for a Linux /boot partition?

And is it safe to not have a /boot partition?

I see some servers don't have a /boot partition while some servers have a 128 MB /boot partition. I am a little confused. Is /boot partition necessary? If it is, how large should it be?

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 /boot partition?

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 /boot partition?

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:

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.