diff --git a/assignment-client/src/AssignmentClientMonitor.cpp b/assignment-client/src/AssignmentClientMonitor.cpp
index 2847d4ebf1..330023dae0 100644
--- a/assignment-client/src/AssignmentClientMonitor.cpp
+++ b/assignment-client/src/AssignmentClientMonitor.cpp
@@ -25,6 +25,9 @@
 #include "AssignmentClientChildData.h"
 #include "SharedUtil.h"
 #include <QtCore/QJsonDocument>
+#ifdef _POSIX_SOURCE
+#include <sys/resource.h>
+#endif
 
 const QString ASSIGNMENT_CLIENT_MONITOR_TARGET_NAME = "assignment-client-monitor";
 const int WAIT_FOR_CHILD_MSECS = 1000;
@@ -71,6 +74,7 @@ AssignmentClientMonitor::AssignmentClientMonitor(const unsigned int numAssignmen
     auto& packetReceiver = DependencyManager::get<NodeList>()->getPacketReceiver();
     packetReceiver.registerListener(PacketType::AssignmentClientStatus, this, "handleChildStatusPacket");
 
+    adjustOSResources(std::max(_numAssignmentClientForks, _maxAssignmentClientForks));
     // use QProcess to fork off a process for each of the child assignment clients
     for (unsigned int i = 0; i < _numAssignmentClientForks; i++) {
         spawnChildClient();
@@ -372,3 +376,27 @@ bool AssignmentClientMonitor::handleHTTPRequest(HTTPConnection* connection, cons
 
     return true;
 }
+
+void AssignmentClientMonitor::adjustOSResources(unsigned int numForks) const
+{
+#ifdef _POSIX_SOURCE
+    // QProcess on Unix uses six (I think) descriptors, some temporarily, for each child proc.
+    // Formula based on tests with a Ubuntu 16.04 VM.
+    unsigned requiredDescriptors = 30 + 6 * numForks;
+    struct rlimit descLimits;
+    if (getrlimit(RLIMIT_NOFILE, &descLimits) == 0) {
+        if (descLimits.rlim_cur < requiredDescriptors) {
+            descLimits.rlim_cur = requiredDescriptors;
+            if (setrlimit(RLIMIT_NOFILE, &descLimits) == 0) {
+                qDebug() << "Resetting descriptor limit to" << requiredDescriptors;
+            } else {
+                const char *const errorString = strerror(errno);
+                qDebug() << "Failed to reset descriptor limit to" << requiredDescriptors << ":" << errorString;
+            }
+        }
+    } else {
+        const char *const errorString = strerror(errno);
+        qDebug() << "Failed to read descriptor limit:" << errorString;
+    }
+#endif
+}
diff --git a/assignment-client/src/AssignmentClientMonitor.h b/assignment-client/src/AssignmentClientMonitor.h
index 8848d503ae..5e32c50e0d 100644
--- a/assignment-client/src/AssignmentClientMonitor.h
+++ b/assignment-client/src/AssignmentClientMonitor.h
@@ -55,6 +55,7 @@ public slots:
 private:
     void spawnChildClient();
     void simultaneousWaitOnChildren(int waitMsecs);
+    void adjustOSResources(unsigned int numForks) const;
 
     QTimer _checkSparesTimer; // every few seconds see if it need fewer or more spare children