Hello,
since yesterday some of my dockers don't start anymore.

Which surprises me. There’s plenty of storage space, etc.

Here for example the log of AdGuard and my diagnostics.

text  error  warn  system  array  login  

2026/03/30 11:30:24.352088 [info] starting adguard home version="AdGuard Home, version v0.107.73"
2026/03/30 11:30:24.354203 [info] dhcpd: warning: creating dhcpv4 server err="dhcpv4: invalid IP is not an IPv4 address"
2026/03/30 11:30:24.354539 [info] tls_manager: using default ciphers
2026/03/30 11:30:24.355283 [info] safesearch: reset rules count=0xcfa360
2026/03/30 11:30:24.356243 [fatal] writing config file: open /opt/adguardhome/conf/.AdGuardHome.yaml3817209365410585793: no space left on device
2026/03/30 11:30:38.306794 [info] starting adguard home version="AdGuard Home, version v0.107.73"
2026/03/30 11:30:38.309744 [info] dhcpd: warning: creating dhcpv4 server err="dhcpv4: invalid IP is not an IPv4 address"
2026/03/30 11:30:38.310053 [info] tls_manager: using default ciphers
2026/03/30 11:30:38.310567 [info] safesearch: reset rules count=0xcfa360
2026/03/30 11:30:38.311786 [fatal] writing config file: open /opt/adguardhome/conf/.AdGuardHome.yaml6758689776098561474: no space left on device
2026/03/30 11:45:10.650826 [info] starting adguard home version="AdGuard Home, version v0.107.73"
2026/03/30 11:45:10.654053 [info] dhcpd: warning: creating dhcpv4 server err="dhcpv4: invalid IP is not an IPv4 address"
2026/03/30 11:45:10.654445 [info] tls_manager: using default ciphers
2026/03/30 11:45:10.655378 [info] safesearch: reset rules count=0xcfa360
2026/03/30 11:45:10.656714 [fatal] writing config file: open /opt/adguardhome/conf/.AdGuardHome.yaml6343088051533144700: no space left on device

tower-diagnostics-20260330-1123.zip

The error message is correct because for appdata (for instance) you have:

shareFloor="98100000"

and you do not have that much free space on the 'cache' pool. Change Minimum Free Space for the share to a lower value or make more space free.

@itimpi You’ve saved the day for me. ❤️

I’ve reduced it to 50 GB and now it’s working again.

As a layman, I’m surprised that such a ‘minor’ error could bring the system to a standstill.

How did you spot my mistake so quickly?

Not sure I agree it is a minor error running out of space on a pool is known to sometimes cause corruption of the pool which can lead to data loss. This is particularly the case when no value is set for the Minimum Free Space so it is getting down to close to zero. The whole idea is to keep the system as a whole functional (which it was as it was just docker having problems) and tell you about the sub-system having problems.

In terms of diagnosis the error messages were complaining about lack of space, so I simply checked the share settings to see how much space you had said needs to be kept free and then how much was actually free.

Note also that there is a Minimum Free Space setting at the pool level as well as the share level, so you might want to check both of them are set appropriately.

@itimpi Thanks for the detailed explanation.

By “minor” errors, I mainly meant how easy they were to fix and why the system can't provide better guidance in those cases.

In any case, thanks again for the great support.

8 minutes ago, Thomas_H said:

@itimpi Thanks for the detailed explanation.

I mainly meant how easy they were to fix and why the system can't provide better guidance in those cases.

The only easy thing I could think of would be to mention checking the Minimum Free Space setting in the message saying it is running out of space. If that was done it could probably distinguish the case where it was the setting at the share level or the pool level that is relevant.