diff --git a/cli/node/cfg.buidler.toml b/cli/node/cfg.buidler.toml
index f2d561e..bfd8675 100644
--- a/cli/node/cfg.buidler.toml
+++ b/cli/node/cfg.buidler.toml
@@ -35,7 +35,7 @@ Symbol = "SUSHI"
 Addr = "0x6b3595068778dd592e39a122f4f5a5cf09c90fe2"
 
 [Debug]
-APIAddress = "localhost:12345"
+APIAddress = "0.0.0.0:12345"
 MeddlerLogs = true
 GinDebugMode = true
 
diff --git a/metric/metric.go b/metric/metric.go
new file mode 100644
index 0000000..a3cc1f5
--- /dev/null
+++ b/metric/metric.go
@@ -0,0 +1,192 @@
+package metric
+
+import (
+	"time"
+
+	"github.com/hermeznetwork/hermez-node/log"
+	"github.com/prometheus/client_golang/prometheus"
+)
+
+type (
+	// Metric represents the metric type
+	Metric string
+)
+
+const (
+	namespaceError      = "error"
+	namespaceSync       = "synchronizer"
+	namespaceTxSelector = "txselector"
+	namespaceAPI        = "api"
+)
+
+var (
+	// Errors errors count metric.
+	Errors = prometheus.NewCounterVec(
+		prometheus.CounterOpts{
+			Namespace: namespaceError,
+			Name:      "errors",
+			Help:      "",
+		}, []string{"error"})
+
+	// WaitServerProof duration time to get the calculated
+	// proof from the server.
+	WaitServerProof = prometheus.NewHistogramVec(
+		prometheus.HistogramOpts{
+			Namespace: namespaceSync,
+			Name:      "wait_server_proof",
+			Help:      "",
+		}, []string{"batch_number", "pipeline_number"})
+
+	// Reorgs block reorg count
+	Reorgs = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Namespace: namespaceSync,
+			Name:      "reorgs",
+			Help:      "",
+		})
+
+	// LastBlockNum last block synced
+	LastBlockNum = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceSync,
+			Name:      "synced_last_block_num",
+			Help:      "",
+		})
+
+	// EthLastBlockNum last eth block synced
+	EthLastBlockNum = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceSync,
+			Name:      "eth_last_block_num",
+			Help:      "",
+		})
+
+	// LastBatchNum last batch synced
+	LastBatchNum = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceSync,
+			Name:      "synced_last_batch_num",
+			Help:      "",
+		})
+
+	// EthLastBatchNum last eth batch synced
+	EthLastBatchNum = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceSync,
+			Name:      "eth_last_batch_num",
+			Help:      "",
+		})
+
+	// GetL2TxSelection L2 tx selection count
+	GetL2TxSelection = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "get_l2_txselection_total",
+			Help:      "",
+		})
+
+	// GetL1L2TxSelection L1L2 tx selection count
+	GetL1L2TxSelection = prometheus.NewCounter(
+		prometheus.CounterOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "get_l1_l2_txselection_total",
+			Help:      "",
+		})
+
+	// SelectedL1CoordinatorTxs selected L1 coordinator tx count
+	SelectedL1CoordinatorTxs = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "selected_l1_coordinator_txs",
+			Help:      "",
+		})
+
+	// SelectedL1UserTxs selected L1 user tx count
+	SelectedL1UserTxs = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "selected_l1_user_txs",
+			Help:      "",
+		})
+
+	// SelectedL2Txs selected L2 tx count
+	SelectedL2Txs = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "selected_l2_txs",
+			Help:      "",
+		})
+
+	// DiscardedL2Txs discarded L2 tx count
+	DiscardedL2Txs = prometheus.NewGauge(
+		prometheus.GaugeOpts{
+			Namespace: namespaceTxSelector,
+			Name:      "discarded_l2_txs",
+			Help:      "",
+		})
+)
+
+func init() {
+	if err := registerCollectors(); err != nil {
+		log.Error(err)
+	}
+}
+func registerCollectors() error {
+	if err := registerCollector(Errors); err != nil {
+		return err
+	}
+	if err := registerCollector(WaitServerProof); err != nil {
+		return err
+	}
+	if err := registerCollector(Reorgs); err != nil {
+		return err
+	}
+	if err := registerCollector(LastBlockNum); err != nil {
+		return err
+	}
+	if err := registerCollector(LastBatchNum); err != nil {
+		return err
+	}
+	if err := registerCollector(EthLastBlockNum); err != nil {
+		return err
+	}
+	if err := registerCollector(EthLastBatchNum); err != nil {
+		return err
+	}
+	if err := registerCollector(GetL2TxSelection); err != nil {
+		return err
+	}
+	if err := registerCollector(GetL1L2TxSelection); err != nil {
+		return err
+	}
+	if err := registerCollector(SelectedL1CoordinatorTxs); err != nil {
+		return err
+	}
+	if err := registerCollector(SelectedL1UserTxs); err != nil {
+		return err
+	}
+	return registerCollector(DiscardedL2Txs)
+}
+
+func registerCollector(collector prometheus.Collector) error {
+	err := prometheus.Register(collector)
+	if err != nil {
+		if _, ok := err.(prometheus.AlreadyRegisteredError); !ok {
+			return err
+		}
+	}
+	return nil
+}
+
+// MeasureDuration measure the method execution duration
+// and save it into a histogram metric
+func MeasureDuration(histogram *prometheus.HistogramVec, start time.Time, lvs ...string) {
+	duration := time.Since(start)
+	histogram.WithLabelValues(lvs...).Observe(float64(duration.Milliseconds()))
+}
+
+// CollectError collect the error message and increment
+// the error count
+func CollectError(err error) {
+	Errors.With(map[string]string{"error": err.Error()}).Inc()
+}
diff --git a/synchronizer/metrics.go b/synchronizer/metrics.go
deleted file mode 100644
index bff876b..0000000
--- a/synchronizer/metrics.go
+++ /dev/null
@@ -1,44 +0,0 @@
-package synchronizer
-
-import "github.com/prometheus/client_golang/prometheus"
-
-var (
-	metricReorgsCount = prometheus.NewCounter(
-		prometheus.CounterOpts{
-			Name: "sync_reorgs",
-			Help: "",
-		},
-	)
-	metricSyncedLastBlockNum = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "sync_synced_last_block_num",
-			Help: "",
-		},
-	)
-	metricEthLastBlockNum = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "sync_eth_last_block_num",
-			Help: "",
-		},
-	)
-	metricSyncedLastBatchNum = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "sync_synced_last_batch_num",
-			Help: "",
-		},
-	)
-	metricEthLastBatchNum = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "sync_eth_last_batch_num",
-			Help: "",
-		},
-	)
-)
-
-func init() {
-	prometheus.MustRegister(metricReorgsCount)
-	prometheus.MustRegister(metricSyncedLastBlockNum)
-	prometheus.MustRegister(metricEthLastBlockNum)
-	prometheus.MustRegister(metricSyncedLastBatchNum)
-	prometheus.MustRegister(metricEthLastBatchNum)
-}
diff --git a/synchronizer/synchronizer.go b/synchronizer/synchronizer.go
index 0d1b9fb..63bb1d5 100644
--- a/synchronizer/synchronizer.go
+++ b/synchronizer/synchronizer.go
@@ -15,6 +15,7 @@ import (
 	"github.com/hermeznetwork/hermez-node/db/statedb"
 	"github.com/hermeznetwork/hermez-node/eth"
 	"github.com/hermeznetwork/hermez-node/log"
+	"github.com/hermeznetwork/hermez-node/metric"
 	"github.com/hermeznetwork/hermez-node/txprocessor"
 	"github.com/hermeznetwork/tracerr"
 )
@@ -549,6 +550,7 @@ func (s *Synchronizer) Sync(ctx context.Context,
 				return nil, nil, tracerr.Wrap(err)
 			}
 			discarded := lastSavedBlock.Num - lastDBBlockNum
+			metric.Reorgs.Inc()
 			return nil, &discarded, nil
 		}
 	}
@@ -641,16 +643,16 @@ func (s *Synchronizer) Sync(ctx context.Context,
 	}
 
 	for _, batchData := range rollupData.Batches {
-		metricSyncedLastBatchNum.Set(float64(batchData.Batch.BatchNum))
-		metricEthLastBatchNum.Set(float64(s.stats.Eth.LastBatchNum))
+		metric.LastBatchNum.Set(float64(batchData.Batch.BatchNum))
+		metric.EthLastBatchNum.Set(float64(s.stats.Eth.LastBatchNum))
 		log.Debugw("Synced batch",
 			"syncLastBatch", batchData.Batch.BatchNum,
 			"syncBatchesPerc", s.stats.batchesPerc(batchData.Batch.BatchNum),
 			"ethLastBatch", s.stats.Eth.LastBatchNum,
 		)
 	}
-	metricSyncedLastBlockNum.Set(float64(s.stats.Sync.LastBlock.Num))
-	metricEthLastBlockNum.Set(float64(s.stats.Eth.LastBlock.Num))
+	metric.LastBlockNum.Set(float64(s.stats.Sync.LastBlock.Num))
+	metric.EthLastBlockNum.Set(float64(s.stats.Eth.LastBlock.Num))
 	log.Debugw("Synced block",
 		"syncLastBlockNum", s.stats.Sync.LastBlock.Num,
 		"syncBlocksPerc", s.stats.blocksPerc(),
diff --git a/txselector/metrics.go b/txselector/metrics.go
deleted file mode 100644
index cb4d780..0000000
--- a/txselector/metrics.go
+++ /dev/null
@@ -1,53 +0,0 @@
-package txselector
-
-import "github.com/prometheus/client_golang/prometheus"
-
-var (
-	metricGetL2TxSelection = prometheus.NewCounter(
-		prometheus.CounterOpts{
-			Name: "txsel_get_l2_txselecton_total",
-			Help: "",
-		},
-	)
-	metricGetL1L2TxSelection = prometheus.NewCounter(
-		prometheus.CounterOpts{
-			Name: "txsel_get_l1_l2_txselecton_total",
-			Help: "",
-		},
-	)
-
-	metricSelectedL1CoordinatorTxs = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "txsel_selected_l1_coordinator_txs",
-			Help: "",
-		},
-	)
-	metricSelectedL1UserTxs = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "txsel_selected_l1_user_txs",
-			Help: "",
-		},
-	)
-	metricSelectedL2Txs = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "txsel_selected_l2_txs",
-			Help: "",
-		},
-	)
-	metricDiscardedL2Txs = prometheus.NewGauge(
-		prometheus.GaugeOpts{
-			Name: "txsel_discarded_l2_txs",
-			Help: "",
-		},
-	)
-)
-
-func init() {
-	prometheus.MustRegister(metricGetL2TxSelection)
-	prometheus.MustRegister(metricGetL1L2TxSelection)
-
-	prometheus.MustRegister(metricSelectedL1CoordinatorTxs)
-	prometheus.MustRegister(metricSelectedL1UserTxs)
-	prometheus.MustRegister(metricSelectedL2Txs)
-	prometheus.MustRegister(metricDiscardedL2Txs)
-}
diff --git a/txselector/txselector.go b/txselector/txselector.go
index 46338b7..1453367 100644
--- a/txselector/txselector.go
+++ b/txselector/txselector.go
@@ -13,6 +13,7 @@ import (
 	"github.com/hermeznetwork/hermez-node/db/l2db"
 	"github.com/hermeznetwork/hermez-node/db/statedb"
 	"github.com/hermeznetwork/hermez-node/log"
+	"github.com/hermeznetwork/hermez-node/metric"
 	"github.com/hermeznetwork/hermez-node/txprocessor"
 	"github.com/hermeznetwork/tracerr"
 	"github.com/iden3/go-iden3-crypto/babyjub"
@@ -123,7 +124,7 @@ func (txsel *TxSelector) coordAccountForTokenID(l1CoordinatorTxs []common.L1Tx,
 // included in the next batch.
 func (txsel *TxSelector) GetL2TxSelection(selectionConfig txprocessor.Config) ([]common.Idx,
 	[][]byte, []common.L1Tx, []common.PoolL2Tx, []common.PoolL2Tx, error) {
-	metricGetL2TxSelection.Inc()
+	metric.GetL2TxSelection.Inc()
 	coordIdxs, accCreationAuths, _, l1CoordinatorTxs, l2Txs,
 		discardedL2Txs, err := txsel.getL1L2TxSelection(selectionConfig, []common.L1Tx{})
 	return coordIdxs, accCreationAuths, l1CoordinatorTxs, l2Txs,
@@ -141,7 +142,7 @@ func (txsel *TxSelector) GetL2TxSelection(selectionConfig txprocessor.Config) ([
 func (txsel *TxSelector) GetL1L2TxSelection(selectionConfig txprocessor.Config,
 	l1UserTxs []common.L1Tx) ([]common.Idx, [][]byte, []common.L1Tx,
 	[]common.L1Tx, []common.PoolL2Tx, []common.PoolL2Tx, error) {
-	metricGetL1L2TxSelection.Inc()
+	metric.GetL1L2TxSelection.Inc()
 	coordIdxs, accCreationAuths, l1UserTxs, l1CoordinatorTxs, l2Txs,
 		discardedL2Txs, err := txsel.getL1L2TxSelection(selectionConfig, l1UserTxs)
 	return coordIdxs, accCreationAuths, l1UserTxs, l1CoordinatorTxs, l2Txs,
@@ -221,10 +222,11 @@ func (txsel *TxSelector) getL1L2TxSelection(selectionConfig txprocessor.Config,
 			return nil, nil, nil, nil, nil, nil, tracerr.Wrap(err)
 		}
 
-		metricSelectedL1UserTxs.Set(float64(len(l1UserTxs)))
-		metricSelectedL1CoordinatorTxs.Set(0)
-		metricSelectedL2Txs.Set(0)
-		metricDiscardedL2Txs.Set(float64(len(discardedL2Txs)))
+		metric.SelectedL1UserTxs.Set(float64(len(l1UserTxs)))
+		metric.SelectedL1CoordinatorTxs.Set(0)
+		metric.SelectedL2Txs.Set(0)
+		metric.DiscardedL2Txs.Set(float64(len(discardedL2Txs)))
+
 		return nil, nil, l1UserTxs, nil, nil, discardedL2Txs, nil
 	}
 
@@ -320,10 +322,10 @@ func (txsel *TxSelector) getL1L2TxSelection(selectionConfig txprocessor.Config,
 		return nil, nil, nil, nil, nil, nil, tracerr.Wrap(err)
 	}
 
-	metricSelectedL1UserTxs.Set(float64(len(l1UserTxs)))
-	metricSelectedL1CoordinatorTxs.Set(float64(len(l1CoordinatorTxs)))
-	metricSelectedL2Txs.Set(float64(len(validTxs)))
-	metricDiscardedL2Txs.Set(float64(len(discardedL2Txs)))
+	metric.SelectedL1CoordinatorTxs.Set(float64(len(l1CoordinatorTxs)))
+	metric.SelectedL1UserTxs.Set(float64(len(l1UserTxs)))
+	metric.SelectedL2Txs.Set(float64(len(validTxs)))
+	metric.DiscardedL2Txs.Set(float64(len(discardedL2Txs)))
 
 	return coordIdxs, accAuths, l1UserTxs, l1CoordinatorTxs, validTxs, discardedL2Txs, nil
 }