diff --git a/.github/ISSUE_TEMPLATE.md b/.github/ISSUE_TEMPLATE.md
index 37dc57e9fa..3050296b7c 100644
--- a/.github/ISSUE_TEMPLATE.md
+++ b/.github/ISSUE_TEMPLATE.md
@@ -5,4 +5,4 @@ When reporting an issue please make sure it contains;
 * A clear description of the issue
 * Any logs or stack traces that you can provide (use a site like https://pastebin.com for larger logs)
 * Steps to reproduce the issue
-* The version/tag/release or commit hash it occured on
\ No newline at end of file
+* The version/tag/release or commit hash it occurred on
diff --git a/node/src/main/kotlin/net/corda/node/internal/NodeStartup.kt b/node/src/main/kotlin/net/corda/node/internal/NodeStartup.kt
index d3fc126f31..a1e6d591eb 100644
--- a/node/src/main/kotlin/net/corda/node/internal/NodeStartup.kt
+++ b/node/src/main/kotlin/net/corda/node/internal/NodeStartup.kt
@@ -35,7 +35,7 @@ import net.corda.node.services.transactions.bftSMaRtSerialFilter
 import net.corda.node.utilities.createKeyPairAndSelfSignedTLSCertificate
 import net.corda.node.utilities.registration.HTTPNetworkRegistrationService
 import net.corda.node.utilities.registration.NodeRegistrationHelper
-import net.corda.node.utilities.registration.UnableToRegisterNodeWithDoormanException
+import net.corda.node.utilities.registration.NodeRegistrationException
 import net.corda.node.utilities.saveToKeyStore
 import net.corda.node.utilities.saveToTrustStore
 import net.corda.nodeapi.internal.addShutdownHook
@@ -154,13 +154,13 @@ open class NodeStartup(val args: Array<String>) {
             if (cmdlineOptions.nodeRegistrationOption != null) {
                 // Null checks for [compatibilityZoneURL], [rootTruststorePath] and [rootTruststorePassword] has been done in [CmdLineOptions.loadConfig]
                 registerWithNetwork(conf, versionInfo, cmdlineOptions.nodeRegistrationOption)
-                // At this point the node registration was succesfull. We can delete the marker file.
+                // At this point the node registration was successful. We can delete the marker file.
                 deleteNodeRegistrationMarker(cmdlineOptions.baseDirectory)
                 return true
             }
             logStartupInfo(versionInfo, cmdlineOptions, conf)
-        } catch (e: UnableToRegisterNodeWithDoormanException) {
-            logger.warn("Node registration service is unavailable. Perhaps try to perform the initial registration again after a while.")
+        } catch (e: NodeRegistrationException) {
+            logger.warn("Node registration service is unavailable. Perhaps try to perform the initial registration again after a while.", e)
             return false
         } catch (e: Exception) {
             logger.error("Exception during node registration", e)
diff --git a/node/src/main/kotlin/net/corda/node/services/statemachine/SingleThreadedStateMachineManager.kt b/node/src/main/kotlin/net/corda/node/services/statemachine/SingleThreadedStateMachineManager.kt
index cc63a6c809..ec37a41aa4 100644
--- a/node/src/main/kotlin/net/corda/node/services/statemachine/SingleThreadedStateMachineManager.kt
+++ b/node/src/main/kotlin/net/corda/node/services/statemachine/SingleThreadedStateMachineManager.kt
@@ -600,10 +600,11 @@ class SingleThreadedStateMachineManager(
     private fun scheduleTimeoutException(flow: Flow, retryCount: Int): ScheduledFuture<*> {
         return with(serviceHub.configuration.flowTimeout) {
             val timeoutDelaySeconds = timeout.seconds * Math.pow(backoffBase, retryCount.toDouble()).toLong()
+            val jitteredDelaySeconds = maxOf(1L, timeoutDelaySeconds/2 + (Math.random() * timeoutDelaySeconds/2).toLong())
             timeoutScheduler.schedule({
                 val event = Event.Error(FlowTimeoutException(maxRestartCount))
                 flow.fiber.scheduleEvent(event)
-            }, timeoutDelaySeconds, TimeUnit.SECONDS)
+            }, jitteredDelaySeconds, TimeUnit.SECONDS)
         }
     }
 
diff --git a/node/src/main/kotlin/net/corda/node/utilities/registration/NetworkRegistrationHelper.kt b/node/src/main/kotlin/net/corda/node/utilities/registration/NetworkRegistrationHelper.kt
index d79c201e6b..db44a402df 100644
--- a/node/src/main/kotlin/net/corda/node/utilities/registration/NetworkRegistrationHelper.kt
+++ b/node/src/main/kotlin/net/corda/node/utilities/registration/NetworkRegistrationHelper.kt
@@ -28,6 +28,7 @@ import org.bouncycastle.openssl.jcajce.JcaPEMWriter
 import org.bouncycastle.util.io.pem.PemObject
 import java.io.IOException
 import java.io.StringWriter
+import java.net.ConnectException
 import java.nio.file.Path
 import java.security.KeyPair
 import java.security.KeyStore
@@ -100,7 +101,14 @@ open class NetworkRegistrationHelper(private val config: SSLConfiguration,
 
         val keyPair = nodeKeyStore.loadOrCreateKeyPair(SELF_SIGNED_PRIVATE_KEY)
 
-        val requestId = submitOrResumeCertificateSigningRequest(keyPair)
+        val requestId = try {
+            submitOrResumeCertificateSigningRequest(keyPair)
+        } catch (e: Exception) {
+            if (e is ConnectException || e is ServiceUnavailableException || e is IOException) {
+                throw NodeRegistrationException(e)
+            }
+            throw e
+        }
 
         val certificates = try {
             pollServerForCertificates(requestId)
@@ -113,7 +121,7 @@ open class NetworkRegistrationHelper(private val config: SSLConfiguration,
         }
         validateCertificates(keyPair.public, certificates)
         storePrivateKeyWithCertificates(nodeKeyStore, keyPair, certificates, keyAlias)
-        onSuccess(keyPair, certificates, tlsCrlIssuerCert?.let { it.subjectX500Principal.toX500Name() })
+        onSuccess(keyPair, certificates, tlsCrlIssuerCert?.subjectX500Principal?.toX500Name())
         // All done, clean up temp files.
         requestIdStore.deleteIfExists()
     }
@@ -193,7 +201,7 @@ open class NetworkRegistrationHelper(private val config: SSLConfiguration,
                 if (idlePeriodDuration != null) {
                     Thread.sleep(idlePeriodDuration.toMillis())
                 } else {
-                    throw UnableToRegisterNodeWithDoormanException()
+                    throw NodeRegistrationException(e)
                 }
             }
         }
@@ -242,7 +250,7 @@ open class NetworkRegistrationHelper(private val config: SSLConfiguration,
     protected open fun isTlsCrlIssuerCertRequired(): Boolean = false
 }
 
-class UnableToRegisterNodeWithDoormanException : IOException()
+class NodeRegistrationException(cause: Throwable?) : IOException("Unable to contact node registration service", cause)
 
 class NodeRegistrationHelper(private val config: NodeConfiguration, certService: NetworkRegistrationService, regConfig: NodeRegistrationOption, computeNextIdleDoormanConnectionPollInterval: (Duration?) -> Duration? = FixedPeriodLimitedRetrialStrategy(10, Duration.ofMinutes(1))) :
         NetworkRegistrationHelper(config,