nextcloud/all-in-one · critical · \Exception

Could not create the nextcloud-aio network: {details}

Error message

Could not create the nextcloud-aio network: {details}

What it means

POST /networks/create for the nextcloud-aio bridge network failed with a RequestException whose code is NOT 409 — 409 (network already exists) is deliberately tolerated as success, making creation idempotent. The daemon's error body is embedded. After creation (or tolerance) the container is connected to this network, so a failure here blocks every container attach.

Source

Thrown at php/src/Docker/DockerActionManager.php:920

        if ($createNetwork) {
            $url = $this->BuildApiUrl('networks/create');
            try {
                $this->sendHttpRequest(
                    'POST',
                    $url,
                    [
                        'json' => [
                            'Name' => $network,
                            'CheckDuplicate' => true,
                            'Driver' => 'bridge',
                            'Internal' => false,
                        ]
                    ]
                );
            } catch (RequestException $e) {
                // 409 is undocumented and gets thrown if the network already exists.
                if ($e->getCode() !== 409) {
                    throw new \Exception("Could not create the nextcloud-aio network: " . $e->getResponse()?->getBody()->getContents());
                }
            }
        }

        $url = $this->BuildApiUrl(
            sprintf('networks/%s/connect', $network)
        );
        $jsonPayload = ['Container' => $id];
        if ($alias !== '') {
            $jsonPayload['EndpointConfig'] = ['Aliases' => [$alias]];
        }

        try {
            $this->sendHttpRequest(
                'POST',
                $url,
                [
                    'json' => $jsonPayload

View on GitHub (pinned to 6b788eec5e)

Solutions

1. List and remove leftovers: docker network ls | grep nextcloud-aio then docker network rm <name>, and retry
2. If pools are exhausted: docker network prune unused networks, or extend default-address-pools in /etc/docker/daemon.json and restart docker
3. Check the daemon logs (journalctl -u docker) for the underlying create failure
4. Verify daemon.json network settings are valid before restarting the daemon

Example fix

// before: create and only tolerate 409
// after: pre-check existence, then create — fully idempotent
try {
    $docker->sendHttpRequest('POST', $docker->BuildApiUrl('networks/create'), [
        'json' => ['Name' => $network, 'CheckDuplicate' => true, 'Driver' => 'bridge', 'Internal' => false]
    ]);
} catch (RequestException $e) {
    if ($e->getCode() !== 409) { throw $e; } // already exists → fine
}

// Check existence first and reuse the existing network instead of creating
$nets = json_decode($docker->sendHttpRequest('GET', $docker->BuildApiUrl('networks'))->getBody(), true) ?: [];
$exists = in_array('nextcloud-aio', array_column($nets, 'Name'), true);
if (!$exists) {
    $docker->sendHttpRequest('POST', $docker->BuildApiUrl('networks/create'), [
        'json' => ['Name' => 'nextcloud-aio', 'CheckDuplicate' => true, 'Driver' => 'bridge', 'Internal' => false]
    ]);
}
// proceed to networks/{name}/connect either way

try {
    createNetworkAndConnect($id, $alias);
} catch (\Exception $e) {
    if (str_contains($e->getMessage(), 'Could not create the nextcloud-aio network')) {
        // address-pool exhaustion is the usual cause: report prune/daemon.json guidance verbatim
        reportNetworkExhaustion($e->getMessage());
    }
    throw $e;
}

When it happens

Trigger: Docker address-pool exhaustion ('all predefined address pools have been fully subnetted') when too many networks exist; daemon/network-driver errors; invalid network configuration in daemon.json; a same-name network in a broken state that 409 does not cover.

Common situations: Hosts running many compose projects or containers exhausting the default 172.17-31.x space; leftover half-created networks; custom default-address-pools config too small.

Related errors

• Could not start container {identifier}: {details}
• Could not create container {identifier}: {details}
• ${DataConst::GetDataDirectory()} does not exist! Something w
• ${DataConst::GetDataDirectory()} does not have enough space
• Could not pull image {imageName} (attempt {attempt}/{maxRetr

AI-assisted analysis of nextcloud/all-in-one@6b788eec5e (2026-08-21). Data as JSON: /api/errors/0d0242d762a788c4. Report an issue: GitHub.