diff --git a/nixos/tests/cassandra.nix b/nixos/tests/cassandra.nix
index aea4fa4d1c95..c55733c9be7b 100644
--- a/nixos/tests/cassandra.nix
+++ b/nixos/tests/cassandra.nix
@@ -8,11 +8,12 @@ let
   jmxRoles = [{ username = "me"; password = "password"; }];
   jmxRolesFile = ./cassandra-jmx-roles;
   jmxAuthArgs = "-u ${(builtins.elemAt jmxRoles 0).username} -pw ${(builtins.elemAt jmxRoles 0).password}";
+  jmxPort = 7200;  # Non-standard port so it doesn't accidentally work
 
   # Would usually be assigned to 512M
   numMaxHeapSize = "400";
   getHeapLimitCommand = ''
-    nodetool info | grep "^Heap Memory" | awk \'{print $NF}\'
+    nodetool info -p ${toString jmxPort} | grep "^Heap Memory" | awk \'{print $NF}\'
   '';
   checkHeapLimitCommand = ''
     [ 1 -eq "$(echo "$(${getHeapLimitCommand}) < ${numMaxHeapSize}" | ${pkgs.bc}/bin/bc)" ]
@@ -27,19 +28,20 @@ let
       package = testPackage;
       maxHeapSize = "${numMaxHeapSize}M";
       heapNewSize = "100M";
+      inherit jmxPort;
     };
-  nodeCfg = ipAddress: extra: {pkgs, config, ...}:
-    { environment.systemPackages = [ testPackage ];
-      networking = {
-        firewall.allowedTCPPorts = [ 7000 7199 9042 ];
-        useDHCP = false;
-        interfaces.eth1.ipv4.addresses = pkgs.lib.mkOverride 0 [
-          { address = ipAddress; prefixLength = 24; }
-        ];
-      };
-      services.cassandra = cassandraCfg ipAddress // extra;
-      virtualisation.memorySize = 1024;
+  nodeCfg = ipAddress: extra: {pkgs, config, ...}: rec {
+    environment.systemPackages = [ testPackage ];
+    networking = {
+      firewall.allowedTCPPorts = [ 7000 9042 services.cassandra.jmxPort ];
+      useDHCP = false;
+      interfaces.eth1.ipv4.addresses = pkgs.lib.mkOverride 0 [
+        { address = ipAddress; prefixLength = 24; }
+      ];
     };
+    services.cassandra = cassandraCfg ipAddress // extra;
+    virtualisation.memorySize = 1024;
+  };
 in
 {
   name = "cassandra-ci";
@@ -50,7 +52,9 @@ in
     cass2 = nodeCfg "192.168.1.3" { jvmOpts = [ "-Dcassandra.replace_address=cass1" ]; };
   };
 
-  testScript = ''
+  testScript = let
+    jmxPortS = toString jmxPort;
+  in ''
     # Check configuration
     subtest "Timers exist", sub {
       $cass0->succeed("systemctl list-timers | grep cassandra-full-repair.timer");
@@ -63,51 +67,51 @@ in
     };
     subtest "Nodetool is operational", sub {
       $cass0->waitForUnit("cassandra.service");
-      $cass0->waitUntilSucceeds("nc -z localhost 7199");
-      $cass0->succeed("nodetool status --resolve-ip | egrep '^UN[[:space:]]+cass0'");
+      $cass0->waitUntilSucceeds("nc -z localhost ${jmxPortS}");
+      $cass0->succeed("nodetool status -p ${jmxPortS} --resolve-ip | egrep '^UN[[:space:]]+cass0'");
     };
     subtest "Cluster name was set", sub {
       $cass0->waitForUnit("cassandra.service");
-      $cass0->waitUntilSucceeds("nc -z localhost 7199");
-      $cass0->waitUntilSucceeds("nodetool describecluster | grep 'Name: ${clusterName}'");
+      $cass0->waitUntilSucceeds("nc -z localhost ${jmxPortS}");
+      $cass0->waitUntilSucceeds("nodetool describecluster -p ${jmxPortS} | grep 'Name: ${clusterName}'");
     };
     subtest "Heap limit set correctly", sub {
       # Nodetool takes a while until it can display info
-      $cass0->waitUntilSucceeds('nodetool info');
+      $cass0->waitUntilSucceeds('nodetool info -p ${jmxPortS}');
       $cass0->succeed('${checkHeapLimitCommand}');
     };
 
     # Check cluster interaction
     subtest "Bring up cluster", sub {
       $cass1->waitForUnit("cassandra.service");
-      $cass1->waitUntilSucceeds("nodetool ${jmxAuthArgs} status | egrep -c '^UN' | grep 2");
-      $cass0->succeed("nodetool status --resolve-ip | egrep '^UN[[:space:]]+cass1'");
+      $cass1->waitUntilSucceeds("nodetool -p ${jmxPortS} ${jmxAuthArgs} status | egrep -c '^UN' | grep 2");
+      $cass0->succeed("nodetool status -p ${jmxPortS} --resolve-ip | egrep '^UN[[:space:]]+cass1'");
     };
   '' + lib.optionalString testRemoteAuth ''
     subtest "Remote authenticated jmx", sub {
       # Doesn't work if not enabled
-      $cass0->waitUntilSucceeds("nc -z localhost 7199");
-      $cass1->fail("nc -z 192.168.1.1 7199");
-      $cass1->fail("nodetool -h 192.168.1.1 status");
+      $cass0->waitUntilSucceeds("nc -z localhost ${jmxPortS}");
+      $cass1->fail("nc -z 192.168.1.1 ${toString jmxPort}");
+      $cass1->fail("nodetool -p ${jmxPortS} -h 192.168.1.1 status");
 
       # Works if enabled
-      $cass1->waitUntilSucceeds("nc -z localhost 7199");
-      $cass0->succeed("nodetool -h 192.168.1.2 ${jmxAuthArgs} status");
+      $cass1->waitUntilSucceeds("nc -z localhost ${toString jmxPort}");
+      $cass0->succeed("nodetool -p ${jmxPortS} -h 192.168.1.2 ${jmxAuthArgs} status");
     };
   '' + ''
     subtest "Break and fix node", sub {
       $cass1->block;
-      $cass0->waitUntilSucceeds("nodetool status --resolve-ip | egrep -c '^DN[[:space:]]+cass1'");
-      $cass0->succeed("nodetool status | egrep -c '^UN'  | grep 1");
+      $cass0->waitUntilSucceeds("nodetool status -p ${jmxPortS} --resolve-ip | egrep -c '^DN[[:space:]]+cass1'");
+      $cass0->succeed("nodetool status -p ${jmxPortS} | egrep -c '^UN'  | grep 1");
       $cass1->unblock;
-      $cass1->waitUntilSucceeds("nodetool ${jmxAuthArgs} status | egrep -c '^UN'  | grep 2");
-      $cass0->succeed("nodetool status | egrep -c '^UN'  | grep 2");
+      $cass1->waitUntilSucceeds("nodetool -p ${jmxPortS} ${jmxAuthArgs} status | egrep -c '^UN'  | grep 2");
+      $cass0->succeed("nodetool status -p ${jmxPortS} | egrep -c '^UN'  | grep 2");
     };
     subtest "Replace crashed node", sub {
       $cass1->crash;
       $cass2->waitForUnit("cassandra.service");
-      $cass0->waitUntilFails("nodetool status --resolve-ip | egrep '^UN[[:space:]]+cass1'");
-      $cass0->waitUntilSucceeds("nodetool status --resolve-ip | egrep '^UN[[:space:]]+cass2'");
+      $cass0->waitUntilFails("nodetool status -p ${jmxPortS} --resolve-ip | egrep '^UN[[:space:]]+cass1'");
+      $cass0->waitUntilSucceeds("nodetool status -p ${jmxPortS} --resolve-ip | egrep '^UN[[:space:]]+cass2'");
     };
   '';
 })