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Re: Moving of stored data



On 3/1/23 09:08, Neal Gompa wrote:
On Wed, Mar 1, 2023 at 9:05 AM Robert Schweikert <rjschwei@xxxxxxxx> wrote:


At present cloud-init stores data in /var/lib/cloud. For systems with
transactional-updates, i.e. opensuse-microos and other incarnations this
location becomes read-only.

Would it be OK to send a PR that moves the data to /var/cache/cloud ?

I'd prefer a wholesale move of the data over various if conditions and
checks whether or not /var/lib is writable. Also we'd know that as of
version X of cloud-init the data has been moved.

Basic idea is

if no os.exists('/var/cache/cloud'):
if os.exists('/var/lib/cloud'):

Do the above early enough in the process such that for all other
locations in the code that access the data the change in location is


That doesn't make any sense. openSUSE systems are explicitly supposed
to omit /var from the read-only root. That's why the RPM and DNF
databases were moved to /usr years ago. The whole point of /var is for
system specific data. It is supposed to be always writable.

Yes of course, I have too many things going on and wasn't paying attention. Thanks for pointing it out.

The move is necessary to preserve the data between snapshots/reboots in a transactional-update system.

/var/lib is discarded between reboots the data in /var/cache is available after reboot into the new snapshot. Meaning if the cloud-init data is not moved then it always looks like a new instance is being booted.


Robert Schweikert                   MAY THE SOURCE BE WITH YOU
Distinguished Engineer                       LINUX
Technical Team Lead Public Cloud
IRC: robjo

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