ray
110 lines
4.0 KiB
Markdown
110 lines
4.0 KiB
Markdown
# Cockpit PackageKit "Cannot refresh cache whilst offline"
|
|
|
|
## Symptoms
|
|
|
|
- Cockpit Software Updates page shows: "Loading available updates failed — Cannot refresh cache whilst offline"
|
|
- `apt-get update` works fine from terminal
|
|
- `nm-online` times out or returns "disconnected"
|
|
|
|
## Root Cause
|
|
|
|
Three independent issues stack:
|
|
|
|
### 1. PackageKit `pk_backend_is_online()` checks NetworkManager
|
|
|
|
PackageKit's apt backend (`/usr/lib/x86_64-linux-gnu/packagekit-backend/libpk_backend_apt.so`) calls `pk_backend_is_online()` which queries NetworkManager's online state via D-Bus. On Ubuntu Server, the default network renderer is **systemd-networkd**, not NetworkManager. The ethernet interface (`enp2s0`) shows as "unmanaged" in NM:
|
|
|
|
```
|
|
nmcli dev status → enp2s0: ethernet, unmanaged
|
|
nmcli general status → STATE: disconnected, CONNECTIVITY: none
|
|
nm-online -q → times out
|
|
```
|
|
|
|
NetworkManager can't claim the interface because systemd-networkd already controls it.
|
|
|
|
### 2. PackageKit needs polkit auth for cache refresh
|
|
|
|
When Cockpit triggers a refresh, PackageKit logs:
|
|
```
|
|
uid 1000 is trying to obtain org.freedesktop.packagekit.system-sources-refresh auth
|
|
uid 1000 failed to obtain auth
|
|
```
|
|
|
|
The default polkit rules require interactive auth for system-sources-refresh.
|
|
|
|
### 3. PackageKit's refresh-cache D-Bus call fails silently
|
|
|
|
Even when auth passes (after polkit fix), the refresh finishes with "failed":
|
|
```
|
|
refresh-cache transaction /8_decaabdd from uid 1000 finished with failed after 126ms
|
|
```
|
|
|
|
The error is generic — `pk_backend_is_online()` returns FALSE, and the backend refuses to refresh.
|
|
|
|
## Diagnosis Commands
|
|
|
|
```bash
|
|
# Check NM state
|
|
nmcli general status
|
|
nm-online -q
|
|
|
|
# Check PackageKit logs
|
|
sudo journalctl -u packagekit --since "5 min ago" --no-pager
|
|
|
|
# Check APT update health
|
|
sudo apt-get update
|
|
|
|
# Trace PackageKit refresh
|
|
sudo journalctl -u packagekit -f &
|
|
dbus-send --system --dest=org.freedesktop.PackageKit \
|
|
--type=method_call /org/freedesktop/PackageKit \
|
|
org.freedesktop.PackageKit.RefreshCache boolean:false
|
|
|
|
# Check available PackageKit backends
|
|
ls /usr/lib/x86_64-linux-gnu/packagekit-backend/
|
|
dpkg -l | grep packagekit
|
|
|
|
# Check apt backend online check
|
|
strings /usr/lib/x86_64-linux-gnu/packagekit-backend/libpk_backend_apt.so | grep -i "offline"
|
|
# Output: pk_backend_is_online, Cannot refresh cache whilst offline
|
|
```
|
|
|
|
## Fix
|
|
|
|
The canonical fix — see `selfhosted-migration` skill, **Phase 6f: Cockpit + PackageKit on systemd-networkd Systems**.
|
|
|
|
### Quick fix (three steps)
|
|
|
|
```bash
|
|
# 1. Stop NM — PackageKit checks NM's state, NM says "disconnected"
|
|
# because systemd-networkd owns the interface
|
|
sudo systemctl mask NetworkManager --now
|
|
|
|
# 2. Verify PackageKit now sees online state
|
|
busctl get-property org.freedesktop.PackageKit /org/freedesktop/PackageKit \
|
|
org.freedesktop.PackageKit NetworkState
|
|
# Expect: u 2 (2 = Online)
|
|
|
|
# 3. Fix polkit so Cockpit can trigger refreshes from the web UI
|
|
sudo tee /etc/polkit-1/rules.d/50-packagekit.rules << 'POLKIT'
|
|
polkit.addRule(function(action, subject) {
|
|
if (action.id == "org.freedesktop.packagekit.system-sources-refresh" &&
|
|
subject.isInGroup("sudo")) {
|
|
return polkit.Result.YES;
|
|
}
|
|
});
|
|
POLKIT
|
|
sudo systemctl restart packagekit
|
|
sudo apt-get update
|
|
```
|
|
|
|
Then reload Cockpit at `https://<server>:9090`.
|
|
|
|
## What NOT to do
|
|
|
|
- **Don't revert to NetworkManager** — NM can't claim an interface managed by systemd-networkd. Setting `managed=true` in NM config doesn't help.
|
|
- **Don't disable systemd-networkd** — it's the default Ubuntu Server network manager and works correctly.
|
|
- **Don't set `Defaults:ray !requiretty` in sudoers** — this flag was removed in newer sudo versions (Ubuntu 26.04+). Use the Python PTY workaround instead.
|
|
- **Don't add NetworkManager connectivity check config** — disabling the NM connectivity check (`interval=0`) doesn't fix PackageKit's internal check.
|
|
- **Don't set `AssumeYes=true` in PackageKit.conf** — it controls auto-answering prompts (like "install these dependencies?"), not the offline check. The offline check is a hard D-Bus query to NetworkManager.
|