0

I'm writing a kickstart script to use when PXE booting to automatically configure new systems with basic settings. I've got everything working except for the partitioning of the boot drive: my /tmp directory is under my / (root) partition instead of a dedicated tmpfs partition. I've found this support article on the topic, but it's locked behind a paywall.

This is what I have so far for partitioning in my kickstart script:

part /boot --fstype=xfs --size=1024 --ondisk=vda
part pv.01 --fstype=lvmpv --size=1 --grow --ondisk=vda

volgroup myvg --pesize=4096 pv.01
logvol swap --vgname=myvg --fstype=swap --recommended --name=swap
logvol / --vgname=myvg --fstype=xfs --grow --size=1024 --name=root

And this is the output of df that it results in:

Filesystem             Size  Used Avail Use% Mounted on
devtmpfs               1.9G     0  1.9G   0% /dev
tmpfs                  1.9G     0  1.9G   0% /dev/shm
tmpfs                  1.9G  8.6M  1.9G   1% /run
tmpfs                  1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/mapper/myvg-root   17G  1.5G   15G  10% /
/dev/vda1              976M  144M  766M  16% /boot
tmpfs                  379M     0  379M   0% /run/user/1000
enpaul
  • 202
  • 2
  • 13

1 Answers1

1

The solution was unrelated to partitioning. The option to mount /tmp as a tmpfs is actually handled by the systemd unit file tmp.mount, so it can be enabled in a kickstart script by enabling tmp.mount in the post install script:

# Run post-install configuration
%post --interpreter=/usr/bin/bash --erroronfail --log=/var/log/kickstart-post.log
systemctl enable tmp.mount
%end

Which results in this df output after boot:

Filesystem             Size  Used Avail Use% Mounted on
devtmpfs               1.9G     0  1.9G   0% /dev
tmpfs                  1.9G     0  1.9G   0% /dev/shm
tmpfs                  1.9G  8.6M  1.9G   1% /run
tmpfs                  1.9G     0  1.9G   0% /sys/fs/cgroup
/dev/mapper/myvg-root   17G  1.5G   15G  10% /
tmpfs                  1.9G  8.0K  1.9G   1% /tmp
/dev/vda1              976M  144M  766M  16% /boot
tmpfs                  379M     0  379M   0% /run/user/1000

This is essentially the inverse of the process documented on the archlinux wiki for disabling this feature.

More info is available on the archlinux wiki, but an important thing to note is that if another partition is already mounted at /tmp then this unit will have no effect, even if it is enabled.

Related reading on the pros/cons of putting /tmp on a tmpfs here: https://access.redhat.com/discussions/688183

enpaul
  • 202
  • 2
  • 13