CA-48995: rather than rely on the pool db backup error preventing forced pool.join...

Signed-off-by: David Scott <dave.scott@eu.citrix.com>

diff --git a/ocaml/xapi/xapi_pool.ml b/ocaml/xapi/xapi_pool.ml
index 1bce625e77b4d1c26fd2576f636efd2ec5b72d50..7d9e4096886182b4187ec1a28910b443ca0ebead 100644 (file)
--- a/ocaml/xapi/xapi_pool.ml
+++ b/ocaml/xapi/xapi_pool.ml
@@ -143,6 +143,25 @@ let pre_join_checks ~__context ~rpc ~session_id ~force =
                        raise (Api_errors.Server_error(Api_errors.pool_joining_host_must_have_physical_managment_nic, []));
                end in
 
+       let assert_product_version_matches () = 
+               let me = Db.Host.get_record ~__context ~self:(Helpers.get_localhost ~__context) in
+               let master_ref = get_master rpc session_id in
+               let master = Client.Host.get_record ~rpc ~session_id ~self:master_ref in
+               let my_software_version = me.API.host_software_version in
+               let master_software_version = master.API.host_software_version in
+               let product_version x = 
+                       if List.mem_assoc "product_version" x
+                       then Some (List.assoc "product_version" x)
+                       else None in
+               let master_product_version = product_version master_software_version in
+               let my_product_version = product_version my_software_version in
+               if master_product_version <> my_product_version then begin
+                       debug "master PRODUCT_VERSION = %s; my PRODUCT_VERSION = %s" 
+                               (Opt.default "Unknown" master_product_version)
+                               (Opt.default "Unknown" my_product_version);
+                       raise (Api_errors.Server_error(Api_errors.pool_joining_host_must_have_same_product_version, []))
+               end in
+
        let assert_hosts_homogeneous () =
                let me = Helpers.get_localhost ~__context in
                let master_ref = get_master rpc session_id in
@@ -264,6 +283,7 @@ let pre_join_checks ~__context ~rpc ~session_id ~force =
        assert_i_know_of_no_other_hosts();
        assert_no_running_vms_on_me ();
        assert_no_vms_with_current_ops ();
+       assert_product_version_matches ();
        if (not force) then assert_hosts_homogeneous ();
        assert_no_shared_srs_on_me ();
        assert_management_interface_is_physical ();
@@ -564,14 +584,11 @@ let join_common ~__context ~master_address ~master_username ~master_password ~fo
                pre_join_checks ~__context ~rpc ~session_id ~force;
                cluster_secret := Client.Pool.initial_auth rpc session_id;
 
-               (* get pool db from new master so I have a backup ready if we failover to me -- if 
-               this fails the whole join operation fails.
-               CA-22449: this is where a --force'd pool.join across differing product versions
-               will fail because the database schema has the wrong version. *)
+               (* get pool db from new master so I have a backup ready if we failover to me *)
                begin try
                        Pool_db_backup.fetch_database_backup ~master_address ~pool_secret:!cluster_secret ~force:None
-               with Api_errors.Server_error(code, _) when code = Api_errors.restore_incompatible_version ->
-                       raise (Api_errors.Server_error(Api_errors.pool_joining_host_must_have_same_product_version, []))
+               with e ->
+                       error "Failed fetching a database backup from the master: %s" (ExnHelper.string_of_exn e)
                end;
 
                (* this is where we try and sync up as much state as we can