[CentOS] [External] /boot partition too small

Thu Oct 12 08:15:13 UTC 2017
Toralf Lund <toralf.lund at pgs.com>

On 11/10/17 15:22, Robert Nichols wrote:
> On 10/11/2017 02:04 AM, Toralf Lund wrote:
>> On 10/10/17 15:55, KM wrote:
>>> First off - let me say I am not an administrator.   I need to 
>>> know if there is an easy way to increase my /boot partition.  When I 
>>> installed CentOS 6 after running 5, it was my oversight not to 
>>> increase the /boot size.  it's too small and I can't do yum updates.
>>> if it's not easy to actually increase it, is it safe to take a chunk 
>>> in my root filesystem (like /new.boot or something) and just mount 
>>> it as /boot from now on so it uses the space or is that not a good 
>>> idea?  I am sure I could easily copy the rpms/kernel stuff over to 
>>> it and then unmounts the real /boot and mount this new area as /boot.
>>> Can you administrators let me know what you think of all this?   
>>> Thanks in advance.
>> Hi,
>>
>> Since a lot of people seem to say none of the above can be done, I'm 
>> starting to feel slightly unsure, but I though gparted could extend, 
>> shrink and move partitions while preserving data.
>
> You would be asking gparted to:
>     1. Reach inside an LVM PV and shrink one filesystem and its LV,
>     2. Rearrange the extents inside the PV to make free space at the 
> beginning,
>     3. Move the start of the PV and adjust all of the starting offsets 
> for the LVs,
>     4. Finally, enlarge partition 1 into the freed-up space.
>
> Even if gparted was willing to attempt that, there is no way I would 
> trust it to do it correctly.
Quite. I'd never try this without a backup, of course. In fact, I've 
only ever used gparted in situations where I had a system dump already. 
Still, it could save you from a bit of work, as in, if it does succeed, 
you won't have to do a full recovery.  Also, I'm not really sure about 
the state of the LVM support, now that you mention it. (But there is 
supposed to be *something* in that area.)

- Toralf