I tried to restore my crashed hap ac^2 from the latest backup file available. Unfortunatelty the size of the backup file is too big for the limited flash (what a decisive decision!) of the device. I had to use an older version of my backups. During this progess I observerd the curiousity that my backup files are actually growing and growing (lately to ~2,2MB). The smallest backup files I spotted from the same device (no maior changes since months) are sized ~0,8MB and can be restored at ease. If I extend the time horizon of my older backups I can see the size of these files jumping up and down with no regularity at all.
What is the reason for the different sizes of the backup files?
Is there any workaround to restore a 2,2MB sized backup file to hap ac^2 ?!?

Put the "Big" backup on an usb flash disk, and insert on the usb port of the hAP²: load from there the bck and you should be good to go.

What is the reason for the different sizes of the backup files?

Probably all the CLI history

Next time use /export file=backup instead of backup, is more portable and undertandable

Put the "Big" backup on an usb flash disk, and insert on the usb port of the hAP²: load from there the bck and you should be good to go.

nice, thanks for hint...

I gonna try that - thx.
The exports are available, but do not include certs an others.

I gonna try that - thx.
The exports are available, but do not include certs an others.

Use this method for backup... :))
viewtopic.php?f=1&t=175360&p=858564#p858564

Same behaviour - RouterOS tries to copy / extract the backup file to internal flash and restore fails. Message box says 'Couldn't restore configuration - action failed (6)'.

your backup is handmade or automatic?
if you try to restore crypted backup on different machine or same netinstalled/resetted fail...

I use a script to store export file and backup file (no password) once a day via ftp on my nas.
The router crashed - I did a netinstall already and could do a successful restore with a version from May, 7th which is only 0,9MB in size.
Since then all stored backup files are sized ~2MB. These can be loaded to flash after I deleted security, advanced and multicast package, but restore fails without any notice.
Since May, 25th the backup files are sized ~2,3MB and cannot be loaded to flash leading to the above error message.

I have a secondary router (RB2011) running with almost the same configuration (VRRP redundancy). It's backup files are ~1MB in size.
My certs are exported and stored in a safe place, but they were issued by the crashed device and cannot be revoked now. This is a minor issue as they are used only internally.

I am just wondering how to avoid backup files to grow above a size which cannot be used to restore the device, because a backup not being able to restore from is useless!
Other option would be to avoid 16MB flash devices ;=)

It's more like something corrupted than a space problem....

Nope - my best guess is, that the size grows with any certificate issued by the device. As you cannot delete issued certificates the size grows until you do a config reset.

Probably you are right,
but I not understand why you use hAP ac^2 as certificate server,
for capsman?