The free space of system partition is insufficient

Synology
1

I was trying to migrate my DS1821+ to DS1825+. It was failed and say insufficient space of system partition. Tried couple restart but can’t fix it so I come back to 1821+ to see if the system run normally. I can login back to 1821+ but the DSM is not working properly now. The file station failed to open and needed repair. But when clicked repair it also saying ‘The free space of system partition is insuficient’ . Not sure what happened and is anyone experience this and know how to fix it. Thank you.

My 1821 originally equipped with two 1TB Samsung cache memory. Additional ram. All 8 bays used with raid 6 setting.

2

What do you see when you run df -h from SSH.

3

Heard of SSH but dont know how. :sweat_smile:

4

Unless you learn, your only option will be to recreate your setup, and restore from your daily backup. Seems you already tried the “reboot and hope” plan. Best.

5

Im having the same issue. Same exact situation and symptoms. its just that im upgrading from 1520+ to 1821+. SSH to NAS confirms 100% usage of system partition. I contacted support about this. Any idea how to clear stuff from System partition?

Screenshot 2026-02-26 1358511
Screenshot 2026-02-26 13585111444×533 18.6 KB

6

Thank you. Tried the reboot and not working. Had contact support and they can remove the occupied space remotely and it’s okay now. Thank you for suggestion on SSH. Will review study in long term.

7

Wait for support reply. They will remote access your NAS to help removing the stuffs in the System partition. Fast.

8

From SSH, post results of:
sudo du -ch -d2 --exclude=./volume1 --exclude=./volume2 --exclude=./proc | sort -h | tail -50