diff --git a/lib/Xud.ts b/lib/Xud.ts
index 490e252c0..d83880e0a 100644
--- a/lib/Xud.ts
+++ b/lib/Xud.ts
@@ -35,9 +35,9 @@ class Xud extends EventEmitter {
   public service!: Service;
   private logger!: Logger;
   private config: Config;
-  private db!: DB;
-  private pool!: Pool;
-  private orderBook!: OrderBook;
+  private db?: DB;
+  private pool?: Pool;
+  private orderBook?: OrderBook;
   private rpcServer?: GrpcServer;
   private httpServer?: HttpServer;
   private grpcAPIProxy?: GrpcWebProxyServer;
@@ -46,6 +46,7 @@ class Xud extends EventEmitter {
   private swapClientManager?: SwapClientManager;
   private unitConverter?: UnitConverter;
   private simnetChannels$?: Subscription;
+  private lockFilePath?: string;
 
   /**
    * Create an Exchange Union daemon.
@@ -88,6 +89,24 @@ class Xud extends EventEmitter {
     }
 
     try {
+      if (this.config.instanceid === 0) {
+        // if we're not running with multiple instances as indicated by an instance id of 0
+        // create a lock file to prevent multiple xud instances from trying to run
+        // with the same node key and/or database
+        const lockFilePath = path.join(this.config.xudir, `${this.config.network}.lock`);
+        try {
+          await (await fs.open(lockFilePath, 'wx')).close();
+          this.lockFilePath = lockFilePath;
+        } catch (err) {
+          if (err.code === 'EEXIST') {
+            this.logger.error(`A lock file exists at ${lockFilePath}. Another xud process is running or a previous process exited ungracefully.`);
+            return;
+          } else {
+            throw err;
+          }
+        }
+      }
+
       if (!this.config.rpc.disable) {
         // start rpc server first, it will respond with UNAVAILABLE error
         // indicating xud is starting until xud finishes initializing
@@ -296,6 +315,10 @@ class Xud extends EventEmitter {
     // TODO: ensure we are not in the middle of executing any trades
     const closePromises: Promise<void>[] = [];
 
+    if (this.lockFilePath) {
+      closePromises.push(fs.unlink(this.lockFilePath).catch(this.logger.error));
+    }
+
     this.simnetChannels$?.unsubscribe();
 
     if (this.swapClientManager) {
@@ -318,7 +341,7 @@ class Xud extends EventEmitter {
     }
     await Promise.all(closePromises);
 
-    await this.db.close();
+    await this.db?.close();
     this.logger.info('XUD shutdown gracefully');
 
     this.emit('shutdown');
diff --git a/lib/service/Service.ts b/lib/service/Service.ts
index f9ded99a7..8e3898a0d 100644
--- a/lib/service/Service.ts
+++ b/lib/service/Service.ts
@@ -5,6 +5,7 @@ import { ProvidePreimageEvent, TransferReceivedEvent } from '../connextclient/ty
 import { OrderSide, Owner, SwapClientType, SwapRole } from '../constants/enums';
 import { OrderAttributes, TradeInstance } from '../db/types';
 import Logger, { Level, LevelPriority } from '../Logger';
+import NodeKey from '../nodekey/NodeKey';
 import OrderBook from '../orderbook/OrderBook';
 import { Currency, isOwnOrder, Order, OrderPortion, OwnLimitOrder, OwnMarketOrder, OwnOrder, PeerOrder, PlaceOrderEvent } from '../orderbook/types';
 import Pool from '../p2p/Pool';
@@ -19,7 +20,6 @@ import { checkDecimalPlaces, sortOrders, toEip55Address } from '../utils/utils';
 import commitHash from '../Version';
 import errors from './errors';
 import { NodeIdentifier, ServiceComponents, ServiceOrder, ServiceOrderSidesArrays, ServicePlaceOrderEvent, ServiceTrade, XudInfo } from './types';
-import NodeKey from 'lib/nodekey/NodeKey';
 
 /** Functions to check argument validity and throw [[INVALID_ARGUMENT]] when invalid. */
 const argChecks = {
diff --git a/test/integration/Service.spec.ts b/test/integration/Service.spec.ts
index 128511dbc..f9b4ed349 100644
--- a/test/integration/Service.spec.ts
+++ b/test/integration/Service.spec.ts
@@ -111,7 +111,7 @@ describe('API Service', () => {
   });
 
   it('should remove an order', () => {
-    const tp = xud['orderBook'].tradingPairs.get('LTC/BTC')!;
+    const tp = xud['orderBook']!.tradingPairs.get('LTC/BTC')!;
     expect(tp.ownOrders.buyMap.has(orderId!)).to.be.true;
     const args = {
       orderId: '1',
diff --git a/test/p2p/networks.spec.ts b/test/p2p/networks.spec.ts
index 81f5dacbe..7e67ec7c2 100644
--- a/test/p2p/networks.spec.ts
+++ b/test/p2p/networks.spec.ts
@@ -18,8 +18,8 @@ describe('P2P Networks Tests', () => {
       await Promise.all([srcNode.start(srcNodeConfig), destNode.start(destNodeConfig)]);
 
       const host = 'localhost';
-      const port = destNode['pool']['listenPort']!;
-      const nodePubKey = destNode['pool'].nodePubKey;
+      const port = destNode['pool']!['listenPort']!;
+      const nodePubKey = destNode['pool']!.nodePubKey;
       const nodeTwoUri = toUri({ host, port, nodePubKey });
 
       const rejectionMsg = `Peer ${nodePubKey}@${host}:${port} closed due to WireProtocolErr framer: incompatible msg origin network (expected: ${srcNodeNetwork}, found: ${destNodeNetwork})`;
@@ -39,11 +39,11 @@ describe('P2P Networks Tests', () => {
       const srcNode = new Xud();
       const destNode = new Xud();
       await Promise.all([srcNode.start(srcNodeConfig), destNode.start(destNodeConfig)]);
-      const srcNodePubKey = srcNode['pool'].nodePubKey;
-      const destNodePubKey = destNode['pool'].nodePubKey;
+      const srcNodePubKey = srcNode['pool']!.nodePubKey;
+      const destNodePubKey = destNode['pool']!.nodePubKey;
 
       const host = 'localhost';
-      const port = destNode['pool']['listenPort']!;
+      const port = destNode['pool']!['listenPort']!;
       const nodeTwoUri = toUri({ host, port, nodePubKey: destNodePubKey });
 
       await expect(srcNode.service.connect({ nodeUri: nodeTwoUri, retryConnecting: false })).to.be.fulfilled;
diff --git a/test/p2p/sanity.spec.ts b/test/p2p/sanity.spec.ts
index 161181ec7..19dac5df0 100644
--- a/test/p2p/sanity.spec.ts
+++ b/test/p2p/sanity.spec.ts
@@ -61,11 +61,11 @@ describe('P2P Sanity Tests', () => {
 
     await Promise.all([nodeOne.start(nodeOneConfig), nodeTwo.start(nodeTwoConfig)]);
 
-    nodeOnePubKey = nodeOne['pool'].nodePubKey;
-    nodeTwoPubKey = nodeTwo['pool'].nodePubKey;
+    nodeOnePubKey = nodeOne['pool']!.nodePubKey;
+    nodeTwoPubKey = nodeTwo['pool']!.nodePubKey;
 
-    nodeTwoPort = nodeTwo['pool']['listenPort']!;
-    nodeOneUri = toUri({ nodePubKey: nodeOnePubKey, host: 'localhost', port: nodeOne['pool']['listenPort']! });
+    nodeTwoPort = nodeTwo['pool']!['listenPort']!;
+    nodeOneUri = toUri({ nodePubKey: nodeOnePubKey, host: 'localhost', port: nodeOne['pool']!['listenPort']! });
     nodeTwoUri = toUri({ nodePubKey: nodeTwoPubKey, host: 'localhost', port: nodeTwoPort });
 
     unusedPort = await getUnusedPort();
@@ -82,13 +82,13 @@ describe('P2P Sanity Tests', () => {
 
   it('should update the node state', (done) => {
     const btcPubKey = '0395033b252c6f40e3756984162d68174e2bd8060a129c0d3462a9370471c6d28f';
-    const nodeTwoPeer = nodeOne['pool'].getPeer(nodeTwoPubKey);
+    const nodeTwoPeer = nodeOne['pool']!.getPeer(nodeTwoPubKey);
     nodeTwoPeer.on('nodeStateUpdate', () => {
       expect(nodeTwoPeer['nodeState']!.lndPubKeys['BTC']).to.equal(btcPubKey);
       done();
     });
 
-    nodeTwo['pool'].updateLndState({
+    nodeTwo['pool']!.updateLndState({
       currency: 'BTC',
       pubKey: btcPubKey,
     });
@@ -100,7 +100,7 @@ describe('P2P Sanity Tests', () => {
   });
 
   it('should disconnect successfully', async () => {
-    await nodeOne['pool']['closePeer'](nodeTwoPubKey, DisconnectionReason.NotAcceptingConnections);
+    await nodeOne['pool']!['closePeer'](nodeTwoPubKey, DisconnectionReason.NotAcceptingConnections);
 
     const listPeersResult = nodeOne.service.listPeers();
     expect(listPeersResult).to.be.empty;