Fix: ensure backward compat config

Fixes: canonical#318

Ensure we populate the config key value db with required values if not
present. Newer microceph version set these values on bootstrap, older
releases might be missing them

Also add some testing for ceph.conf

Signed-off-by: Peter Sabaini <[email protected]>

.github/workflows/q2q-candidate-upgrade.yml

@@ -58,5 +58,8 @@ jobs:
     - name: Wait until 3 OSDs are up
       run:  ~/actionutils.sh headexec wait_for_osds 3
 
+    - name: Verify config
+      run: ~/actionutils.sh test_ceph_conf
+
     - name: Exercise RGW again
       run: ~/actionutils.sh headexec testrgw

.github/workflows/q2r-candidate-upgrade.yaml

@@ -58,5 +58,8 @@ jobs:
     - name: Wait until 3 OSDs are up
       run:  ~/actionutils.sh headexec wait_for_osds 3
 
+    - name: Verify config
+      run: ~/actionutils.sh test_ceph_conf
+
     - name: Exercise RGW again
       run: ~/actionutils.sh headexec testrgw

.github/workflows/r2r-candidate-upgrade.yaml

@@ -58,5 +58,8 @@ jobs:
     - name: Wait until 3 OSDs are up
       run:  ~/actionutils.sh headexec wait_for_osds 3
 
+    - name: Verify config
+      run: ~/actionutils.sh test_ceph_conf
+
     - name: Exercise RGW again
       run: ~/actionutils.sh headexec testrgw

.github/workflows/tests.yml

@@ -255,6 +255,9 @@ jobs:
     - name: Setup cluster
       run: ~/actionutils.sh cluster_nodes custom
 
+    - name: Verify config
+      run: ~/actionutils.sh test_ceph_conf
+
     - name: Add 2 OSDs
       run: |
         for c in node-wrk1 node-wrk2 ; do
@@ -489,4 +492,3 @@ jobs:
 
     - name: Exercise RGW again
       run: ~/actionutils.sh headexec testrgw
-

microceph/ceph/config.go

@@ -6,6 +6,7 @@ import (
 	"encoding/json"
 	"fmt"
 	"github.com/canonical/microceph/microceph/interfaces"
+	"net"
 	"os"
 	"path/filepath"
 	"strings"
@@ -162,43 +163,104 @@ func ListConfigs() (types.Configs, error) {
 	return configs, nil
 }
 
-// updates the ceph config file.
-func UpdateConfig(s interfaces.StateInterface) error {
-	confPath := filepath.Join(os.Getenv("SNAP_DATA"), "conf")
-	runPath := filepath.Join(os.Getenv("SNAP_DATA"), "run")
+// backwardCompatPubnet ensures that the public_network is set in the database
+// this is a backward-compat shim to accomodate older versions of microceph
+// which will ensure that the public_network is set in the database
+func backwardCompatPubnet(s interfaces.StateInterface) error {
+	config, err := getConfigDb(s)
+	if err != nil {
+		return fmt.Errorf("failed to get config from db: %w", err)
+	}
 
-	// Get the configuration and servers.
+	// do we have a public_network configured?
+	pubNet := config["public_network"]
+	_, _, err = net.ParseCIDR(pubNet)
+	if err != nil {
+		// get public network from default address
+		pubNet, err = common.Network.FindNetworkAddress(s.ClusterState().Address().Hostname())
+		if err != nil {
+			return fmt.Errorf("failed to locate public network: %w", err)
+		}
+		// update the database
+		err = s.ClusterState().Database.Transaction(s.ClusterState().Context, func(ctx context.Context, tx *sql.Tx) error {
+			_, err = database.CreateConfigItem(ctx, tx, database.ConfigItem{Key: "public_network", Value: pubNet})
+			if err != nil {
+				return fmt.Errorf("failed to record public_network: %w", err)
+			}
+			return nil
+		})
+	}
+
+	return nil
+}
+
+// backwardCompatMonitors retrieves monitor addresses from the node list and returns that
+// this a backward-compat shim to accomodate older versions of microceph
+func backwardCompatMonitors(s interfaces.StateInterface) ([]string, error) {
 	var err error
-	var configItems []database.ConfigItem
+	var monitors []database.Service
+	serviceName := "mon"
 
 	err = s.ClusterState().Database.Transaction(s.ClusterState().Context, func(ctx context.Context, tx *sql.Tx) error {
-		configItems, err = database.GetConfigItems(ctx, tx)
+		monitors, err = database.GetServices(ctx, tx, database.ServiceFilter{Service: &serviceName})
 		if err != nil {
 			return err
 		}
-
 		return nil
 	})
 	if err != nil {
-		return err
+		return nil, err
 	}
 
-	config := map[string]string{}
-	for _, item := range configItems {
-		config[item.Key] = item.Value
+	monitorAddresses := make([]string, len(monitors))
+	remotes := s.ClusterState().Remotes().RemotesByName()
+	for i, monitor := range monitors {
+		remote, ok := remotes[monitor.Member]
+		if !ok {
+			continue
+		}
+		monitorAddresses[i] = remote.Address.Addr().String()
+	}
+	return monitorAddresses, nil
+}
+
+// UpdateConfig updates the ceph.conf file with the current configuration.
+func UpdateConfig(s interfaces.StateInterface) error {
+	confPath := filepath.Join(os.Getenv("SNAP_DATA"), "conf")
+	runPath := filepath.Join(os.Getenv("SNAP_DATA"), "run")
+
+	err := backwardCompatPubnet(s)
+	if err != nil {
+		return fmt.Errorf("failed to ensure backward compat: %w", err)
+	}
+
+	config, err := getConfigDb(s)
+	if err != nil {
+		return fmt.Errorf("failed to get config db: %w", err)
 	}
 
 	// REF: https://docs.ceph.com/en/quincy/rados/configuration/network-config-ref/#ceph-daemons
 	// The mon host configuration option only needs to be sufficiently up to date such that a
 	// client can reach one monitor that is currently online.
 	monitorAddresses := getMonitorAddresses(config)
+
+	// backward compat: if no mon hosts found, get them from the node addresses but don't
+	// insert into db, as the join logic will take care of that.
+	if len(monitorAddresses) == 0 {
+		monitorAddresses, err = backwardCompatMonitors(s)
+		if err != nil {
+			return fmt.Errorf("failed to get monitor addresses: %w", err)
+		}
+	}
+
 	conf := newCephConfig(confPath)
 
 	// Check if host has IP address on the configured public network.
 	_, err = common.Network.FindIpOnSubnet(config["public_network"])
 	if err != nil {
 		return fmt.Errorf("failed to locate IP on public network %s: %w", config["public_network"], err)
 	}
+
 	clientConfig, err := GetClientConfigForHost(s, s.ClusterState().Name())
 	if err != nil {
 		logger.Errorf("Failed to pull Client Configurations: %v", err)
@@ -225,6 +287,7 @@ func UpdateConfig(s interfaces.StateInterface) error {
 	if err != nil {
 		return fmt.Errorf("couldn't render ceph.conf: %w", err)
 	}
+	logger.Debugf("updated ceph.conf: %v", conf.GetPath())
 
 	// Generate ceph.client.admin.keyring
 	keyring := newCephKeyring(confPath, "ceph.keyring")
@@ -242,6 +305,30 @@ func UpdateConfig(s interfaces.StateInterface) error {
 	return nil
 }
 
+// getConfigDb retrieves the configuration from the database.
+func getConfigDb(s interfaces.StateInterface) (map[string]string, error) {
+	var err error
+	var configItems []database.ConfigItem
+
+	err = s.ClusterState().Database.Transaction(s.ClusterState().Context, func(ctx context.Context, tx *sql.Tx) error {
+		configItems, err = database.GetConfigItems(ctx, tx)
+		if err != nil {
+			return err
+		}
+
+		return nil
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	config := map[string]string{}
+	for _, item := range configItems {
+		config[item.Key] = item.Value
+	}
+	return config, nil
+}
+
 // getMonitorAddresses scans a provided config key/value map and returns a list of mon hosts found.
 func getMonitorAddresses(configs map[string]string) []string {
 	monHosts := []string{}

microceph/ceph/start.go

@@ -3,6 +3,7 @@ package ceph
 import (
 	"context"
 	"database/sql"
+	"github.com/canonical/lxd/shared/logger"
 	"github.com/canonical/microceph/microceph/interfaces"
 	"reflect"
 	"time"
@@ -19,6 +20,7 @@ func Start(s interfaces.StateInterface) error {
 		for {
 			// Check that the database is ready.
 			if !s.ClusterState().Database.IsOpen() {
+				logger.Debug("start: database not ready, waiting...")
 				time.Sleep(10 * time.Second)
 				continue
 			}
@@ -39,26 +41,28 @@ func Start(s interfaces.StateInterface) error {
 				return nil
 			})
 			if err != nil {
+				logger.Warnf("start: failed to fetch monitors, retrying: %v", err)
 				time.Sleep(10 * time.Second)
 				continue
 			}
 
 			// Compare to the previous list.
 			if reflect.DeepEqual(oldMonitors, monitors) {
+				logger.Debugf("start: monitors unchanged, sleeping: %v", monitors)
 				time.Sleep(time.Minute)
 				continue
 			}
 
 			err = UpdateConfig(s)
 			if err != nil {
+				logger.Errorf("start: failed to update config, retrying: %v", err)
 				time.Sleep(10 * time.Second)
 				continue
 			}
-
+			logger.Debug("start: updated config, sleeping")
 			oldMonitors = monitors
 			time.Sleep(time.Minute)
 		}
-
 	}()
 
 	return nil

tests/scripts/actionutils.sh

@@ -388,6 +388,31 @@ function test_migration() {
     return -1
 }
 
+function test_ceph_conf() {
+    set -uex
+    for n in $( lxc ls -c n --format csv ); do
+        echo "checking node $n"
+        lxc exec $n -- sh <<'EOF'
+# Test: configured rundir must be current
+current=$( realpath /var/snap/microceph/current )
+rundir=$( cat /var/snap/microceph/current/conf/ceph.conf | awk '/run dir/{ print $4 }' )
+p=$( dirname $rundir )
+if [ $p != $current ]; then
+    echo "Error: snap data dir $current, configured run dir: $rundir"
+    cat /var/snap/microceph/current/conf/ceph.conf
+    exit -1
+fi
+
+# Test: must contain public_network
+if ! grep -q public_net /var/snap/microceph/current/conf/ceph.conf ; then
+    echo "Error: didn't find public_net in ceph.conf"
+    cat /var/snap/microceph/current/conf/ceph.conf
+    exit -1
+fi
+EOF
+    done
+}
+
 function headexec() {
     local run="${1?missing}"
     shift