Grow a partition

[PapaParrot]

This :

parrot$ df -h
Filesystem     Size    Used   Avail Capacity  Mounted on
/dev/sd0a     1005M   1005M  -50.0M   105%    /
/dev/sd0k      797G    429G    328G    57%    /home
/dev/sd0d      3.9G    4.7M    3.7G     0%    /tmp
/dev/sd0f      2.0G    1.0G    882M    54%    /usr
/dev/sd0g     1005M    223M    732M    23%    /usr/X11R6
/dev/sd0h     19.7G    5.1G   13.6G    27%    /usr/local
/dev/sd0j      5.9G    2.0K    5.6G     0%    /usr/obj
/dev/sd0i      2.0G    2.0K    1.9G     0%    /usr/src
/dev/sd0e      7.6G    572M    6.7G     8%    /var

Speaks for it's self. One time , along time ago I did successfully grow my "sd0k" /home partition, it was fairly simple. But I have forgotten exactly how, and also the sd0a / partition is different. I do know there is info in the FAQ, and also 'man fdisk', etc. How ever, I am really not in very good health at all, and would appreciate if any one can give me a straight forward , step by step. Mostly to confirm if what I think is best.
My thoughts are to shrink, or take from sd0k /home, aprox 2g and then grow sd0a / adding 2g to it, ...
Thank you

[shywren]

Normally, the root partition shouldn't fill up, and being full indicates that something has gone wrong. Which is to say... do you know why / has ended up this way? On my -current system, df -h returns the following for the root partition:

Filesystem     Size    Used   Avail Capacity  Mounted on
/dev/sd0a     1005M    126M    829M    13%    /

Full root partitions occasionally come up on the mailing lists, though I'm having trouble finding the threads I'm thinking of at the moment. One thread I did manage to find suggested that a dd gone wrong is a common cause of a full /, though I think I've also seen other explanations in the past. This might be a better place to start, especially given that... resizing partitions on OpenBSD is *not* trivial, and a fresh install is the general rule of thumb, iirc.

[Head_on_a_Stick]

The sysutils/ncdu package is very useful for analysing disk usage.

[fvgit]

In any case growfs(8) and disklabel(8) are your tools to grow a partition on OpenBSD:

     The growfs utility extends the newfs(8) program.  Before starting growfs,
     the partition must be set to a larger size using disklabel(8).  The
     growfs utility extends the size of the file system on the specified
     special file.

     Currently growfs can only enlarge unmounted file systems.  Do not try
     enlarging a mounted file system - your system may panic and you will not
     be able to use the file system any longer.  Most of the newfs(8) options
     cannot be changed by growfs.  In fact, you can only increase the size of
     the file system.  Use tunefs(8) for other changes.

(...)

[PapaParrot]

shywren > Normally, the root partition shouldn't fill up, and being full indicates that something has gone wrong.

I know, that is something else that has me worried about this, no I don't know why, it is a surprise.

. resizing partitions on OpenBSD is *not* trivial, and a fresh install is the general rule of thumb, iirc.

Well, it depends, years ago I needed to grow the /home partition, and it was not very difficult, but like I said , I don't remember much about it, however being that this is sd0a / , it may not be trivial,
I noticed it because I had wanted to install "cmake", and it could not install:

parrot$ su
Password:
parrot# pkg_add cmake
quirks-3.325 signed on 2020-08-21T22:26:57Z
|No change in quirks-3.325
cmake-3.16.2p1v0:libuv-1.30.1: ok
Error: /dev/sd0a on / is not large enough (/etc/rhashrc)
/dev/sd0a on /: 523 bytes (missing 102378 blocks)
/dev/sd0h on /usr/local: 2347692 bytes
cmake-3.16.2p1v0:jsoncpp-1.8.4p2: ok
Can't install cmake-3.16.2p1v0: can't resolve rhash-1.3.9
Couldn't install cmake-3.16.2p1v0 rhash-1.3.9
parrot#

[PapaParrot]

Thanks, I looked at the thread on the mailing list, all though I still do not know how it got that way, I did fix it , at least for now:

parrot$ su
Password:
parrot# find -x / -size +10000 -exec du -h {} \;
17.8M   /bsd
9.9M    /bsd.rd
886M    /mnt/tempfile
17.7M   /bsd.sp
17.8M   /bsd.booted
9.8M    /bsd.rd-6.5
parrot# cd /mnt
parrot# ls
tempfile
parrot# cd tempfile
ksh: cd: /mnt/tempfile - Not a directory
parrot# rm tempfile
parrot# df -h
Filesystem     Size    Used   Avail Capacity  Mounted on
/dev/sd0a     1005M    118M    836M    12%    /
/dev/sd0k      797G    429G    328G    57%    /home
/dev/sd0d      3.9G    6.5M    3.7G     0%    /tmp
/dev/sd0f      2.0G    1.0G    884M    54%    /usr
/dev/sd0g     1005M    223M    732M    23%    /usr/X11R6
/dev/sd0h     19.7G    5.1G   13.6G    27%    /usr/local
/dev/sd0j      5.9G    2.0K    5.6G     0%    /usr/obj
/dev/sd0i      2.0G    2.0K    1.9G     0%    /usr/src
/dev/sd0e      7.6G    572M    6.7G     8%    /var
parrot#

Thanks


Edit: Now I remember, I did run a 'dd' command, and that is what created the "886M /mnt/tempfile",
so it was a dd command gone bad,...dummy me, I will blame the medications for it.
And thanks again, including every one that responded.

[shywren]

Ah, wonderful! I'm finding it challenging to think of just the right search terms to use on marc.info to get more on this (as I cannot for the life of me remember the contexts in which I've seen lots of discussion about this very topic in the past; maybe syspatch?), so it's good to know I can stop digging