diff --git a/test/failover/failover.result b/test/failover/failover.result
index ef31a5d1..0e40e1ed 100644
--- a/test/failover/failover.result
+++ b/test/failover/failover.result
@@ -120,15 +120,15 @@ priority_order()
   - - 1
     - unknown zone
 ...
-vshard.router.route(1).uuid == rs_uuid[1]
+vshard.router.route(1)._replicaset.uuid == rs_uuid[1]
 ---
 - true
 ...
-vshard.router.route(31).uuid == rs_uuid[2]
+vshard.router.route(31)._replicaset.uuid == rs_uuid[2]
 ---
 - true
 ...
-vshard.router.route(61).uuid == rs_uuid[3]
+vshard.router.route(61)._replicaset.uuid == rs_uuid[3]
 ---
 - true
 ...
@@ -371,15 +371,15 @@ priority_order()
   - - 1
     - unknown zone
 ...
-vshard.router.route(1).uuid == rs_uuid[1]
+vshard.router.route(1)._replicaset.uuid == rs_uuid[1]
 ---
 - true
 ...
-vshard.router.route(31).uuid == rs_uuid[2]
+vshard.router.route(31)._replicaset.uuid == rs_uuid[2]
 ---
 - true
 ...
-vshard.router.route(61).uuid == rs_uuid[3]
+vshard.router.route(61)._replicaset.uuid == rs_uuid[3]
 ---
 - true
 ...
@@ -409,15 +409,15 @@ priority_order()
   - - 1
     - unknown zone
 ...
-vshard.router.route(1).uuid == rs_uuid[1]
+vshard.router.route(1)._replicaset.uuid == rs_uuid[1]
 ---
 - true
 ...
-vshard.router.route(31).uuid == rs_uuid[2]
+vshard.router.route(31)._replicaset.uuid == rs_uuid[2]
 ---
 - true
 ...
-vshard.router.route(61).uuid == rs_uuid[3]
+vshard.router.route(61)._replicaset.uuid == rs_uuid[3]
 ---
 - true
 ...
@@ -447,15 +447,15 @@ priority_order()
   - - unknown zone
     - 1
 ...
-vshard.router.route(1).uuid == rs_uuid[1]
+vshard.router.route(1)._replicaset.uuid == rs_uuid[1]
 ---
 - true
 ...
-vshard.router.route(31).uuid == rs_uuid[2]
+vshard.router.route(31)._replicaset.uuid == rs_uuid[2]
 ---
 - true
 ...
-vshard.router.route(61).uuid == rs_uuid[3]
+vshard.router.route(61)._replicaset.uuid == rs_uuid[3]
 ---
 - true
 ...
@@ -482,7 +482,7 @@ while not test_run:grep_log('router_1', 'Ping error from', 1000) do fiber.sleep(
 t = string.rep('a', 1024 * 1024 * 500)
 ---
 ...
-rs = vshard.router.route(31)
+rs = vshard.router.route(31)._replicaset
 ---
 ...
 while rs.master ~= rs.replica do fiber.sleep(0.01) end
diff --git a/test/failover/failover.test.lua b/test/failover/failover.test.lua
index d054853f..7693bf9e 100644
--- a/test/failover/failover.test.lua
+++ b/test/failover/failover.test.lua
@@ -55,9 +55,9 @@ test_run:switch('router_1')
 vshard.router.cfg(cfg)
 while not test_run:grep_log('router_1', 'New replica box_1_d%(storage%@') do fiber.sleep(0.1) end
 priority_order()
-vshard.router.route(1).uuid == rs_uuid[1]
-vshard.router.route(31).uuid == rs_uuid[2]
-vshard.router.route(61).uuid == rs_uuid[3]
+vshard.router.route(1)._replicaset.uuid == rs_uuid[1]
+vshard.router.route(31)._replicaset.uuid == rs_uuid[2]
+vshard.router.route(61)._replicaset.uuid == rs_uuid[3]
 vshard.router.call(1, 'read', 'echo', {123})
 test_run:switch('box_1_d')
 -- Not 0 - 'read' echo was called here.
@@ -145,27 +145,27 @@ create_router('router_2')
 test_run:switch('router_2')
 vshard.router.cfg(cfg)
 priority_order()
-vshard.router.route(1).uuid == rs_uuid[1]
-vshard.router.route(31).uuid == rs_uuid[2]
-vshard.router.route(61).uuid == rs_uuid[3]
+vshard.router.route(1)._replicaset.uuid == rs_uuid[1]
+vshard.router.route(31)._replicaset.uuid == rs_uuid[2]
+vshard.router.route(61)._replicaset.uuid == rs_uuid[3]
 test_run:switch('default')
 
 create_router('router_3')
 test_run:switch('router_3')
 vshard.router.cfg(cfg)
 priority_order()
-vshard.router.route(1).uuid == rs_uuid[1]
-vshard.router.route(31).uuid == rs_uuid[2]
-vshard.router.route(61).uuid == rs_uuid[3]
+vshard.router.route(1)._replicaset.uuid == rs_uuid[1]
+vshard.router.route(31)._replicaset.uuid == rs_uuid[2]
+vshard.router.route(61)._replicaset.uuid == rs_uuid[3]
 test_run:switch('default')
 
 create_router('router_4')
 test_run:switch('router_4')
 vshard.router.cfg(cfg)
 priority_order()
-vshard.router.route(1).uuid == rs_uuid[1]
-vshard.router.route(31).uuid == rs_uuid[2]
-vshard.router.route(61).uuid == rs_uuid[3]
+vshard.router.route(1)._replicaset.uuid == rs_uuid[1]
+vshard.router.route(31)._replicaset.uuid == rs_uuid[2]
+vshard.router.route(61)._replicaset.uuid == rs_uuid[3]
 
 --
 -- gh-169: do not close connections on too long ping when this is
@@ -178,7 +178,7 @@ vshard.router.cfg(cfg)
 while not test_run:grep_log('router_1', 'Ping error from', 1000) do fiber.sleep(0.01) end
 
 t = string.rep('a', 1024 * 1024 * 500)
-rs = vshard.router.route(31)
+rs = vshard.router.route(31)._replicaset
 while rs.master ~= rs.replica do fiber.sleep(0.01) end
 future = nil
 -- Create strong reference to prevent Lua GC from closing the
diff --git a/test/misc/check_uuid_on_connect.result b/test/misc/check_uuid_on_connect.result
index 19f46d9c..92df215b 100644
--- a/test/misc/check_uuid_on_connect.result
+++ b/test/misc/check_uuid_on_connect.result
@@ -199,7 +199,7 @@ vshard.router.route(1)
   bucket_id: 1
 ...
 -- Ok to work with correct replicasets.
-vshard.router.route(2).uuid
+vshard.router.route(2)._replicaset.uuid
 ---
 - cbf06940-0790-498b-948d-042b62cf3d29
 ...
diff --git a/test/misc/check_uuid_on_connect.test.lua b/test/misc/check_uuid_on_connect.test.lua
index cf383727..1a0b8879 100644
--- a/test/misc/check_uuid_on_connect.test.lua
+++ b/test/misc/check_uuid_on_connect.test.lua
@@ -74,7 +74,7 @@ test_run:switch('bad_uuid_router')
 vshard.router.static.route_map[1] = nil
 vshard.router.route(1)
 -- Ok to work with correct replicasets.
-vshard.router.route(2).uuid
+vshard.router.route(2)._replicaset.uuid
 
 _ = test_run:cmd("switch default")
 test_run:cmd('stop server bad_uuid_router')
diff --git a/test/multiple_routers/multiple_routers.result b/test/multiple_routers/multiple_routers.result
index 9a932852..cd4e5655 100644
--- a/test/multiple_routers/multiple_routers.result
+++ b/test/multiple_routers/multiple_routers.result
@@ -79,11 +79,6 @@ vshard.router.call(1, 'read', 'do_select', {1})
 ---
 - [[1, 1]]
 ...
--- Test that static router is just a router object under the hood.
-vshard.router.static:route(1) == vshard.router.route(1)
----
-- true
-...
 -- Configure extra router.
 router_2 = vshard.router.new('router_2', configs.cfg_2)
 ---
diff --git a/test/multiple_routers/multiple_routers.test.lua b/test/multiple_routers/multiple_routers.test.lua
index e9be6b71..564108a1 100644
--- a/test/multiple_routers/multiple_routers.test.lua
+++ b/test/multiple_routers/multiple_routers.test.lua
@@ -30,9 +30,6 @@ _ = test_run:cmd("switch router_1")
 vshard.router.call(1, 'write', 'do_replace', {{1, 1}})
 vshard.router.call(1, 'read', 'do_select', {1})
 
--- Test that static router is just a router object under the hood.
-vshard.router.static:route(1) == vshard.router.route(1)
-
 -- Configure extra router.
 router_2 = vshard.router.new('router_2', configs.cfg_2)
 router_2:bootstrap()
diff --git a/test/router-luatest/map_callrw_test.lua b/test/router-luatest/map_callrw_test.lua
index 7d225f8d..8ec25717 100644
--- a/test/router-luatest/map_callrw_test.lua
+++ b/test/router-luatest/map_callrw_test.lua
@@ -212,6 +212,7 @@ g.test_map_part_double_ref = function(cg)
         -- Make sure the location of the bucket is known.
         local rs, err = ivshard.router.route(bid)
         ilt.assert_equals(err, nil)
+        rs = rs._replicaset
         ilt.assert_equals(rs.uuid, uuid)
     end, {bid1, cg.rs1_uuid})
     -- Then, move the bucket form rs1 to rs2. Now the router has an outdated
@@ -251,7 +252,7 @@ g.test_map_part_double_ref = function(cg)
             ivshard.router.discovery_wakeup()
             local rs, err = ivshard.router.route(bid)
             ilt.assert_equals(err, nil)
-            ilt.assert_equals(rs.uuid, uuid)
+            ilt.assert_equals(rs._replicaset.uuid, uuid)
         end)
     end, {bid1, cg.rs1_uuid})
 end
@@ -273,7 +274,7 @@ g.test_map_part_ref_timeout = function(cg)
             for _, bid in ipairs(bids) do
                 local rs, err = ivshard.router.route(bid)
                 ilt.assert_equals(err, nil)
-                ilt.assert_equals(rs.uuid, uuid)
+                ilt.assert_equals(rs._replicaset.uuid, uuid)
             end
         end
     end, {{[cg.rs1_uuid] = {bid1, bid2}, [cg.rs2_uuid] = {bid3, bid4}}})
@@ -379,7 +380,7 @@ g.test_map_part_ref_timeout = function(cg)
             ivshard.router.discovery_wakeup()
             local rs, err = ivshard.router.route(bid)
             ilt.assert_equals(err, nil)
-            ilt.assert_equals(rs.uuid, uuid)
+            ilt.assert_equals(rs._replicaset.uuid, uuid)
         end)
     end, {bid2, cg.rs1_uuid})
 end
diff --git a/test/router-luatest/router_2_2_test.lua b/test/router-luatest/router_2_2_test.lua
index 7736dd04..6f8a4c25 100644
--- a/test/router-luatest/router_2_2_test.lua
+++ b/test/router-luatest/router_2_2_test.lua
@@ -122,6 +122,65 @@ g.test_msgpack_args = function(g)
     t.assert_equals(res, 100, 'good result')
 end
 
+local function router_check_replicaset_protection_init()
+    g.router:exec(function()
+        rawset(_G, "check_replicaset_protection",
+            function(rs)
+                t.assert_not_equals(rs._replicaset, nil)
+                t.assert_equals(next(rs, next(rs)), nil)
+                t.assert_not_equals(rs.call, nil)
+                t.assert_not_equals(rs.callrw, nil)
+                t.assert_not_equals(rs.callro, nil)
+                t.assert_not_equals(rs.callbro, nil)
+                t.assert_not_equals(rs.callre, nil)
+                t.assert_not_equals(rs.callbre, nil)
+                local err_msg =
+                    "Modification of replicaset table is not allowed"
+                -- Adding a field is prohibited.
+                t.assert_error_msg_contains(
+                    err_msg, function(t) t.new_field = 1 end, rs)
+                err_msg = "cannot change a protected metatable"
+                t.assert_error_msg_equals(err_msg, setmetatable, rs, {})
+            end)
+    end)
+end
+
+local function router_check_replicaset_protection_clear()
+    g.router:exec(function()
+        rawset(_G, "check_replicaset_protection", nil)
+    end)
+end
+
+g.test_router_route_return_value_protection = function(g)
+    router_check_replicaset_protection_init()
+    g.router:exec(function()
+        _G.check_replicaset_protection(ivshard.router.route(1))
+    end)
+    router_check_replicaset_protection_clear()
+end
+
+g.test_router_routeall_return_value_protection = function(g)
+    router_check_replicaset_protection_init()
+    g.router:exec(function()
+        local replicasets = ivshard.router.routeall()
+        for _, rs in pairs(replicasets) do
+            _G.check_replicaset_protection(rs)
+        end
+        -- Adding a field.
+        replicasets.new_field = 1
+        t.assert_equals(replicasets.new_field, 1)
+        replicasets = ivshard.router.routeall()
+        t.assert_equals(replicasets.new_field, nil)
+        -- Deleting a field.
+        local id, _ = next(replicasets)
+        replicasets[id] = nil
+        t.assert_equals(replicasets[id], nil)
+        replicasets = ivshard.router.routeall()
+        t.assert_not_equals(replicasets[id], nil)
+    end)
+    router_check_replicaset_protection_clear()
+end
+
 local function test_return_raw_template(g, mode)
     --
     -- Normal call.
@@ -1083,7 +1142,7 @@ g.test_retryable_transfer_in_progress = function(g)
     end)
     g.router:exec(function(bid, uuid)
         local rs = ivshard.router.route(bid)
-        ilt.assert_equals(rs.uuid, uuid)
+        ilt.assert_equals(rs._replicaset.uuid, uuid)
     end, {bid, g.replica_2_a:replicaset_uuid()})
 
     -- Block bucket receive.
diff --git a/test/router-luatest/router_election_auto_master_test.lua b/test/router-luatest/router_election_auto_master_test.lua
index 336d4cb9..7efc9855 100644
--- a/test/router-luatest/router_election_auto_master_test.lua
+++ b/test/router-luatest/router_election_auto_master_test.lua
@@ -67,7 +67,8 @@ end)
 local function router_wait_for_leader(bid, uuid)
     ilt.helpers.retrying({timeout = ivtest.wait_timeout}, function()
         ivshard.router.master_search_wakeup()
-        ilt.assert_equals(ivshard.router.route(bid).master.uuid, uuid)
+        ilt.assert_equals(
+            ivshard.router.route(bid)._replicaset.master.uuid, uuid)
     end)
 end
 
diff --git a/test/router/reload.result b/test/router/reload.result
index ce6780d5..93d72008 100644
--- a/test/router/reload.result
+++ b/test/router/reload.result
@@ -203,7 +203,7 @@ check_reloaded()
 --
 -- Outdate old replicaset and replica objects.
 --
-rs = vshard.router.route(1)
+rs = vshard.router.route(1)._replicaset
 ---
 ...
 rs:callro('echo', {'some_data'})
@@ -233,7 +233,7 @@ rs.callro(rs, 'echo', {'some_data'})
 vshard.router = require('vshard.router')
 ---
 ...
-rs = vshard.router.route(1)
+rs = vshard.router.route(1)._replicaset
 ---
 ...
 rs:callro('echo', {'some_data'})
@@ -258,7 +258,7 @@ cfg.connection_outdate_delay = old_connection_delay
 vshard.router.static.connection_outdate_delay = nil
 ---
 ...
-rs_new = vshard.router.route(1)
+rs_new = vshard.router.route(1)._replicaset
 ---
 ...
 rs_old = rs
diff --git a/test/router/reload.test.lua b/test/router/reload.test.lua
index 57c71b47..aab1825e 100644
--- a/test/router/reload.test.lua
+++ b/test/router/reload.test.lua
@@ -114,7 +114,7 @@ check_reloaded()
 --
 -- Outdate old replicaset and replica objects.
 --
-rs = vshard.router.route(1)
+rs = vshard.router.route(1)._replicaset
 rs:callro('echo', {'some_data'})
 package.loaded["vshard.router"] = nil
 _ = require('vshard.router')
@@ -122,7 +122,7 @@ _ = require('vshard.router')
 while not rs.is_outdated do fiber.sleep(0.001) end
 rs.callro(rs, 'echo', {'some_data'})
 vshard.router = require('vshard.router')
-rs = vshard.router.route(1)
+rs = vshard.router.route(1)._replicaset
 rs:callro('echo', {'some_data'})
 -- Test `connection_outdate_delay`.
 old_connection_delay = cfg.connection_outdate_delay
@@ -130,7 +130,7 @@ cfg.connection_outdate_delay = 0.3
 vshard.router.cfg(cfg)
 cfg.connection_outdate_delay = old_connection_delay
 vshard.router.static.connection_outdate_delay = nil
-rs_new = vshard.router.route(1)
+rs_new = vshard.router.route(1)._replicaset
 rs_old = rs
 _, replica_old = next(rs_old.replicas)
 rs_new:callro('echo', {'some_data'})
diff --git a/test/router/router.result b/test/router/router.result
index 0425b3a9..1a6112d1 100644
--- a/test/router/router.result
+++ b/test/router/router.result
@@ -454,7 +454,7 @@ util.check_error(vshard.router.route)
 ---
 - 'Usage: router.route(bucket_id)'
 ...
-conn = vshard.router.route(1).master.conn
+conn = vshard.router.route(1)._replicaset.master.conn
 ---
 ...
 conn.state
@@ -482,7 +482,7 @@ rs.master = master
 master.conn:close()
 ---
 ...
-conn = vshard.router.route(1):connect()
+conn = vshard.router.route(1)._replicaset:connect()
 ---
 ...
 conn:wait_connected()
diff --git a/test/router/router.test.lua b/test/router/router.test.lua
index c71b9d46..ccb70a80 100644
--- a/test/router/router.test.lua
+++ b/test/router/router.test.lua
@@ -169,7 +169,7 @@ _ = test_run:cmd('start server storage_2_a')
 vshard.router.route(vshard.consts.DEFAULT_BUCKET_COUNT + 100)
 util.check_error(vshard.router.route, 'asdfg')
 util.check_error(vshard.router.route)
-conn = vshard.router.route(1).master.conn
+conn = vshard.router.route(1)._replicaset.master.conn
 conn.state
 -- Test missing master.
 rs = vshard.router.static.replicasets[util.replicasets[2]]
@@ -179,7 +179,7 @@ vshard.router.route(1).master
 rs.master = master
 -- Test reconnect on bucker_route().
 master.conn:close()
-conn = vshard.router.route(1):connect()
+conn = vshard.router.route(1)._replicaset:connect()
 conn:wait_connected()
 conn.state
 
diff --git a/test/router/router2.result b/test/router/router2.result
index 684d8d60..5a0db964 100644
--- a/test/router/router2.result
+++ b/test/router/router2.result
@@ -352,7 +352,7 @@ vshard.consts.REPLICA_BACKOFF_INTERVAL = 0.1
  | ...
 
 -- Indeed fails when called directly via netbox.
-conn = vshard.router.route(1).master.conn
+conn = vshard.router.route(1)._replicaset.master.conn
  | ---
  | ...
 ok, err = pcall(conn.call, conn, 'vshard.storage.call',                         \
@@ -473,7 +473,7 @@ test_run:switch('router_1')
  | ---
  | - true
  | ...
-conn = vshard.router.route(1).master.conn
+conn = vshard.router.route(1)._replicaset.master.conn
  | ---
  | ...
 ok, err = pcall(conn.call, conn, 'vshard.storage.call',                         \
diff --git a/test/router/router2.test.lua b/test/router/router2.test.lua
index c5e0dd31..5abb59c0 100644
--- a/test/router/router2.test.lua
+++ b/test/router/router2.test.lua
@@ -139,7 +139,7 @@ test_run:switch('router_1')
 vshard.consts.REPLICA_BACKOFF_INTERVAL = 0.1
 
 -- Indeed fails when called directly via netbox.
-conn = vshard.router.route(1).master.conn
+conn = vshard.router.route(1)._replicaset.master.conn
 ok, err = pcall(conn.call, conn, 'vshard.storage.call',                         \
                 {1, 'read', 'echo', {1}})
 assert(not ok and err.code == box.error.ACCESS_DENIED)
@@ -188,7 +188,7 @@ vshard.storage.call = nil
 
 -- Indeed fails when called directly via netbox.
 test_run:switch('router_1')
-conn = vshard.router.route(1).master.conn
+conn = vshard.router.route(1)._replicaset.master.conn
 ok, err = pcall(conn.call, conn, 'vshard.storage.call',                         \
                 {1, 'read', 'echo', {1}})
 assert(not ok and err.code == box.error.NO_SUCH_PROC)
diff --git a/vshard/replicaset.lua b/vshard/replicaset.lua
index d3bf0dba..b7df5f3f 100644
--- a/vshard/replicaset.lua
+++ b/vshard/replicaset.lua
@@ -1568,6 +1568,42 @@ local function cluster_calculate_etalon_balance(replicasets, bucket_count)
     end
 end
 
+local replicaset_public_mt = {
+    __index = {
+        call = function(self, ...)
+            return self._replicaset:call(...)
+        end,
+        callrw = function(self, ...)
+            return self._replicaset:callrw(...)
+        end,
+        callro = function(self, ...)
+            return self._replicaset:callro(...)
+        end,
+        callbro = function(self, ...)
+            return self._replicaset:callbro(...)
+        end,
+        callre = function(self, ...)
+            return self._replicaset:callre(...)
+        end,
+        callbre = function(self, ...)
+            return self._replicaset:callbre(...)
+        end,
+    },
+    __newindex = function()
+        error("Modification of replicaset table is not allowed")
+    end,
+    __metatable = "Replicaset table is protected",
+}
+
+local function make_replicasets_public(replicasets)
+    local replicasets_public = {}
+    for key, rs in pairs(replicasets) do
+        replicasets_public[key] =
+            setmetatable({ _replicaset = rs, }, replicaset_public_mt)
+    end
+    return replicasets_public
+end
+
 --
 -- Update/build replicasets from configuration
 --
@@ -2147,5 +2183,6 @@ return {
     create_workers = create_workers,
     locate_masters = locate_masters,
     -- Functions, exported for testing.
-    _worker_service_to_func = worker_service_to_func
+    _worker_service_to_func = worker_service_to_func,
+    make_replicasets_public = make_replicasets_public,
 }
diff --git a/vshard/router/init.lua b/vshard/router/init.lua
index d748585d..c74610b1 100644
--- a/vshard/router/init.lua
+++ b/vshard/router/init.lua
@@ -1168,7 +1168,11 @@ local function router_route(router, bucket_id)
     if type(bucket_id) ~= 'number' then
         error('Usage: router.route(bucket_id)')
     end
-    return bucket_resolve(router, bucket_id)
+    local replicaset, err = bucket_resolve(router, bucket_id)
+    if replicaset == nil then
+        return nil, err
+    end
+    return router.replicasets_public[replicaset.id], err
 end
 
 --
@@ -1176,7 +1180,7 @@ end
 -- @retval See self.replicasets map.
 --
 local function router_routeall(router)
-    return router.replicasets
+    return table.copy(router.replicasets_public)
 end
 
 --------------------------------------------------------------------------------
@@ -1269,6 +1273,9 @@ local function router_cfg(router, cfg, is_reload)
     router.total_bucket_count = vshard_cfg.bucket_count
     router.current_cfg = cfg
     router.replicasets = new_replicasets
+    router.replicasets_public =
+        lreplicaset.make_replicasets_public(new_replicasets)
+    router.failover_ping_timeout = vshard_cfg.failover_ping_timeout
     router.sync_timeout = vshard_cfg.sync_timeout
     local old_route_map = router.route_map
     local known_bucket_count = 0