diff --git a/ocaml/tests/test_vm_helpers.ml b/ocaml/tests/test_vm_helpers.ml
index bdd8dc061d8..4aa506c3ddf 100644
--- a/ocaml/tests/test_vm_helpers.ml
+++ b/ocaml/tests/test_vm_helpers.ml
@@ -159,7 +159,7 @@ let rec assert_equivalent expected_grouping actual_grouping =
       assert_host_groups_equal e g ;
       assert_equivalent es gs
 
-let assert_host_groups_equal_for_vgpu g g' =
+let assert_host_groups_equal g g' =
   match g' with
   | [] ->
       ()
@@ -170,7 +170,7 @@ let assert_host_groups_equal_for_vgpu g g' =
       Alcotest.(check (slist string String.compare))
         "check host strings" (extract_host_strings g) (extract_host_strings g')
 
-let rec assert_equivalent_for_vgpu expected_grouping actual_grouping =
+let rec assert_equivalent_for_grouping expected_grouping actual_grouping =
   match (expected_grouping, actual_grouping) with
   | [], [] ->
       ()
@@ -181,19 +181,23 @@ let rec assert_equivalent_for_vgpu expected_grouping actual_grouping =
       Alcotest.fail
         (Printf.sprintf "%d fewer groups than expected." (List.length xx))
   | e :: es, g :: gs ->
-      assert_host_groups_equal_for_vgpu e g ;
-      assert_equivalent_for_vgpu es gs
+      assert_host_groups_equal e g ;
+      assert_equivalent_for_grouping es gs
 
 let assert_grouping ~__context gpu_group ~visible_hosts vgpu_type g =
   let vgpu = VGPU_T.make_vgpu ~__context ~gPU_group:gpu_group vgpu_type in
   let host_lists = rank_hosts_by_best_vgpu ~__context vgpu visible_hosts in
-  assert_equivalent_for_vgpu g host_lists
+  assert_equivalent_for_grouping g host_lists
 
 let check_expectations ~__context gpu_group visible_hosts vgpu_type
     expected_grouping =
   assert_grouping ~__context gpu_group ~visible_hosts vgpu_type
     expected_grouping
 
+let check_anti_affinity_grouping ~__context ~vm ~group expected_grouping =
+  let host_lists = rank_hosts_by_placement ~__context ~vm ~group in
+  assert_equivalent_for_grouping expected_grouping host_lists
+
 let test_group_hosts_bf () =
   on_pool_of_k1s
     VGPU_T.(
@@ -524,6 +528,28 @@ let test_group_hosts_netsriov_with_allocated () =
             "Test-failure: Unexpected number of sriov network in test"
   )
 
+let test_get_group_key_anti_affinity () =
+  let __context = T.make_test_database () in
+  let vm = T.make_vm ~__context () in
+  let group = T.make_vm_group ~__context ~placement:`anti_affinity () in
+  Db.VM.set_groups ~__context ~self:vm ~value:[group] ;
+  match Xapi_vm_helpers.get_group_key ~__context ~vm with
+  | `AntiAffinity _ ->
+      ()
+  | _ ->
+      Alcotest.fail "Test-failure: Unexpected Group Key in test"
+
+let test_get_group_key_normal_group () =
+  let __context = T.make_test_database () in
+  let vm = T.make_vm ~__context () in
+  let normal_group = T.make_vm_group ~__context ~placement:`normal () in
+  Db.VM.set_groups ~__context ~self:vm ~value:[normal_group] ;
+  match Xapi_vm_helpers.get_group_key ~__context ~vm with
+  | `Other ->
+      ()
+  | _ ->
+      Alcotest.fail "Test-failure: Unexpected Group Key in test"
+
 let test_get_group_key_vgpu () =
   on_pool_of_intel_i350 (fun __context _ _ _ ->
       let group = List.hd (Db.GPU_group.get_all ~__context) in
@@ -573,6 +599,352 @@ let test_get_group_key_vgpu_and_netsriov () =
           Alcotest.fail "Test-failure: Unexpected Group Key in test"
   )
 
+let test_get_group_key_anti_affinity_and_vgpu_and_netsriov () =
+  on_pool_of_intel_i350 (fun __context _ _ _ ->
+      let group = List.hd (Db.GPU_group.get_all ~__context) in
+      let vm = make_vm_with_vgpu_in_group ~__context VGPU_T.k100 group in
+      let sriov_network =
+        List.find
+          (fun network ->
+            Xapi_network_sriov_helpers.is_sriov_network ~__context ~self:network
+          )
+          (Db.Network.get_all ~__context)
+      in
+      let (_ : API.ref_VIF) =
+        T.make_vif ~__context ~vM:vm ~network:sriov_network ()
+      in
+      let anti_affinity_group =
+        T.make_vm_group ~__context ~placement:`anti_affinity ()
+      in
+      Db.VM.set_groups ~__context ~self:vm ~value:[anti_affinity_group] ;
+      match Xapi_vm_helpers.get_group_key ~__context ~vm with
+      | `AntiAffinity _ ->
+          ()
+      | _ ->
+          Alcotest.fail "Test-failure: Unexpected Group Key in test"
+  )
+
+type vm_info = {name: string; host: string; group: string; state: string}
+
+type vm_anti_affinity_ranked_grp_test_case = {
+    description: string
+  ; vm_to_start: vm_info
+  ; other_vms: vm_info list
+  ; hosts: string list
+  ; affinity_host: string
+  ; expected: string list list
+}
+
+let vm_anti_affinity_ranked_grp_test_cases =
+  [
+    {
+      description= "No other VM"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms= []
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ; {
+      description= "VMs not in group"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h2"; group= ""; state= "running"}
+        ; {name= "vm2"; host= "h3"; group= ""; state= "running"}
+        ; {name= "vm3"; host= "h3"; group= ""; state= "running"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ; {
+      description= "VMs in other group"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h2"; group= "other-group"; state= "running"}
+        ; {name= "vm2"; host= "h3"; group= "other-group"; state= "running"}
+        ; {name= "vm3"; host= "h3"; group= "other-group"; state= "running"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ; {
+      description= "3 running VMs (h1(0) h2(1) h3(2))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h2"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm2"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm3"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"]; ["h2"]; ["h3"]]
+    }
+  ; {
+      description= "3 running VMs (h1(1) h2(1) h3(1))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h1"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm2"; host= "h2"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm3"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ; {
+      description= "3 running VMs (h1(0) h2(0) h3(3))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm2"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm3"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"]; ["h3"]]
+    }
+  ; {
+      description= "3 starting VMs (h1(0) h2(1) h3(2))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h2"; group= "anti-affinity"; state= "starting"}
+        ; {name= "vm2"; host= "h3"; group= "anti-affinity"; state= "starting"}
+        ; {name= "vm3"; host= "h3"; group= "anti-affinity"; state= "starting"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"]; ["h2"]; ["h3"]]
+    }
+  ; {
+      description= "3 starting VMs (h1(1) h2(1) h3(1))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h1"; group= "anti-affinity"; state= "starting"}
+        ; {name= "vm2"; host= "h2"; group= "anti-affinity"; state= "starting"}
+        ; {name= "vm3"; host= "h3"; group= "anti-affinity"; state= "starting"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ; {
+      description= "3 starting VMs (h1(0) h2(0) h3(3))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h3"; group= "anti-affinity"; state= "starting"}
+        ; {name= "vm2"; host= "h3"; group= "anti-affinity"; state= "starting"}
+        ; {name= "vm3"; host= "h3"; group= "anti-affinity"; state= "starting"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"]; ["h3"]]
+    }
+  ; {
+      description= "3 stopped VMs"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= ""; group= "anti-affinity"; state= "halted"}
+        ; {name= "vm2"; host= ""; group= "anti-affinity"; state= "halted"}
+        ; {name= "vm3"; host= ""; group= "anti-affinity"; state= "halted"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ; {
+      description= "3 suspended VMs"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= ""; group= "anti-affinity"; state= "suspended"}
+        ; {name= "vm2"; host= ""; group= "anti-affinity"; state= "suspended"}
+        ; {name= "vm3"; host= ""; group= "anti-affinity"; state= "suspended"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ; {
+      description= "3 paused VMs (h1(0) h2(1) h3(2))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h2"; group= "anti-affinity"; state= "paused"}
+        ; {name= "vm2"; host= "h3"; group= "anti-affinity"; state= "paused"}
+        ; {name= "vm3"; host= "h3"; group= "anti-affinity"; state= "paused"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ; {
+      description= "3 running VMs with affinity-host"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h1"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm2"; host= "h2"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm3"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= "h1"
+    ; expected= [["h1"]; ["h2"; "h3"]]
+    }
+  ; {
+      description= "6 running VMs (h1(1) h2(2) h3(3))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h1"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm2"; host= "h2"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm3"; host= "h2"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm4"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm5"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm6"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"]; ["h2"]; ["h3"]]
+    }
+  ; {
+      description= "6 running VMs (h1(2) h2(2) h3(2))"
+    ; vm_to_start=
+        {name= "vm"; host= ""; group= "anti-affinity"; state= "halted"}
+    ; other_vms=
+        [
+          {name= "vm1"; host= "h1"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm2"; host= "h1"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm3"; host= "h2"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm4"; host= "h2"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm5"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ; {name= "vm6"; host= "h3"; group= "anti-affinity"; state= "running"}
+        ]
+    ; hosts= ["h1"; "h2"; "h3"]
+    ; affinity_host= ""
+    ; expected= [["h1"; "h2"; "h3"]]
+    }
+  ]
+
+let make_hosts ~__context ~hosts =
+  match hosts with
+  | fst :: others ->
+      let host1 = List.hd (Db.Host.get_all ~__context) in
+      Db.Host.set_name_label ~__context ~self:host1 ~value:fst ;
+      List.iter
+        (fun h ->
+          let _ = T.make_host ~__context ~name_label:h () in
+          ()
+        )
+        others
+  | [] ->
+      ()
+
+let make_vm_based_on_vm_info ~__context ~vm_info =
+  let vm = T.make_vm ~__context ~name_label:vm_info.name () in
+  ( match vm_info.group with
+  | "" ->
+      ()
+  | group_name ->
+      let group =
+        match Db.VM_group.get_by_name_label ~__context ~label:group_name with
+        | g :: _ ->
+            g
+        | [] ->
+            T.make_vm_group ~__context ~placement:`anti_affinity
+              ~name_label:group_name ()
+      in
+      Db.VM.set_groups ~__context ~self:vm ~value:[group]
+  ) ;
+  ( match vm_info.host with
+  | "" ->
+      ()
+  | host_name -> (
+      let host =
+        List.hd (Db.Host.get_by_name_label ~__context ~label:host_name)
+      in
+      match vm_info.state with
+      | "running" ->
+          Db.VM.set_power_state ~__context ~self:vm ~value:`Running ;
+          Db.VM.set_resident_on ~__context ~self:vm ~value:host
+      | "starting" ->
+          Db.VM.set_power_state ~__context ~self:vm ~value:`Halted ;
+          Db.VM.set_scheduled_to_be_resident_on ~__context ~self:vm ~value:host
+      | "suspended" ->
+          Db.VM.set_power_state ~__context ~self:vm ~value:`Suspended
+      | "paused" ->
+          Db.VM.set_power_state ~__context ~self:vm ~value:`Paused ;
+          Db.VM.set_resident_on ~__context ~self:vm ~value:host
+      | "halted" ->
+          Db.VM.set_power_state ~__context ~self:vm ~value:`Halted
+      | _ ->
+          ()
+    )
+  ) ;
+  vm
+
+let test_vm_anti_affinity_ranked_grp
+    {vm_to_start; other_vms; hosts; affinity_host; expected; _} () =
+  let __context = T.make_test_database () in
+  make_hosts ~__context ~hosts ;
+  let vm = make_vm_based_on_vm_info ~__context ~vm_info:vm_to_start in
+  let _ =
+    List.map
+      (fun vm -> make_vm_based_on_vm_info ~__context ~vm_info:vm)
+      other_vms
+  in
+  Db.VM.set_affinity ~__context ~self:vm
+    ~value:
+      ( match affinity_host with
+      | "" ->
+          Ref.null
+      | host_name ->
+          List.hd (Db.Host.get_by_name_label ~__context ~label:host_name)
+      ) ;
+  let group = Db.VM.get_groups ~__context ~self:vm |> List.hd in
+  check_anti_affinity_grouping ~__context ~vm ~group
+    (List.map
+       (fun list ->
+         List.map
+           (fun host_name ->
+             List.hd (Db.Host.get_by_name_label ~__context ~label:host_name)
+           )
+           list
+       )
+       expected
+    )
+
+let generate_vm_anti_affinity_ranked_grp_tests case =
+  (case.description, `Quick, test_vm_anti_affinity_ranked_grp case)
+
+let anti_affinity_tests =
+  List.map generate_vm_anti_affinity_ranked_grp_tests
+    vm_anti_affinity_ranked_grp_test_cases
+
 let test =
   [
     ("test_gpus_available_succeeds", `Quick, test_gpus_available_succeeds)
@@ -612,14 +984,24 @@ let test =
     , `Quick
     , test_group_hosts_netsriov_with_allocated
     )
+  ; ( "test_get_group_key_anti_affinity"
+    , `Quick
+    , test_get_group_key_anti_affinity
+    )
+  ; ("test_get_group_key_normal_group", `Quick, test_get_group_key_normal_group)
   ; ("test_get_group_key_vgpu", `Quick, test_get_group_key_vgpu)
   ; ("test_get_group_key_netsriov", `Quick, test_get_group_key_netsriov)
   ; ( "test_get_group_key_vgpu_and_netsriov"
     , `Quick
     , test_get_group_key_vgpu_and_netsriov
     )
+  ; ( "test_get_group_key_anti_affinity_and_vgpu_and_netsriov"
+    , `Quick
+    , test_get_group_key_anti_affinity_and_vgpu_and_netsriov
+    )
   ]
 
 let () =
   Suite_init.harness_init () ;
-  Alcotest.run "Test VM Helpers suite" [("Test_vm_helpers", test)]
+  Alcotest.run "Test VM Helpers suite"
+    [("Test_vm_helpers", test @ anti_affinity_tests)]
diff --git a/quality-gate.sh b/quality-gate.sh
index 6659ae24def..483033b9a8a 100755
--- a/quality-gate.sh
+++ b/quality-gate.sh
@@ -3,7 +3,7 @@
 set -e
 
 list-hd () {
-  N=318
+  N=324
   LIST_HD=$(git grep -r --count 'List.hd' -- **/*.ml | cut -d ':' -f 2 | paste -sd+ - | bc)
   if [ "$LIST_HD" -eq "$N" ]; then
     echo "OK counted $LIST_HD List.hd usages"