diff --git a/Framework/test/testCcdbDatabase.cxx b/Framework/test/testCcdbDatabase.cxx
index b716b99b4a..fb045b3a4f 100644
--- a/Framework/test/testCcdbDatabase.cxx
+++ b/Framework/test/testCcdbDatabase.cxx
@@ -50,6 +50,16 @@ using namespace o2::quality_control::core;
 using namespace o2::quality_control::repository;
 using namespace std;
 
+// A QC-specific CCDB instance: ali-qcdb-test by default. It holds different
+// objects from ccdb-test -- see the TODO in testTimekeeper.cxx -- so this is
+// deliberately NOT ALICEO2_CCDB_HOST. ALICEO2_QCDB_HOST lets a network-isolated
+// build container reach it through a broker instead; unset, behaviour is
+// unchanged.
+const std::string QCDB_ENDPOINT = [] {
+  const char* host = std::getenv("ALICEO2_QCDB_HOST");
+  return std::string((host && *host) ? host : "ali-qcdb-test.cern.ch:8083");
+}();
+
 // These tests upload, so this has to be a WRITABLE instance -- ccdb-test by
 // default. ALICEO2_CCDB_HOST lets a network-isolated build container reach one
 // through a broker instead; unset, behaviour is unchanged.
@@ -360,7 +370,7 @@ BOOST_AUTO_TEST_CASE(ccdb_test_thread_api, *utf::depends_on("ccdb_store"))
 BOOST_AUTO_TEST_CASE(ccdb_test_no_thread_api)
 {
   unique_ptr<o2::ccdb::CcdbApi> api = std::make_unique<o2::ccdb::CcdbApi>();
-  string ccdbUrl = "http://ali-qcdb-test.cern.ch:8083";
+  string ccdbUrl = "http://" + QCDB_ENDPOINT;
   api->init(ccdbUrl);
   cout << "ccdb url: " << ccdbUrl << endl;
   bool hostReachable = api->isHostReachable();
diff --git a/Framework/test/testDbFactory.cxx b/Framework/test/testDbFactory.cxx
index 2d567032bc..bfa60b012d 100644
--- a/Framework/test/testDbFactory.cxx
+++ b/Framework/test/testDbFactory.cxx
@@ -33,10 +33,21 @@
 #include <QualityControl/RepoPathUtils.h>
 #include <QualityControl/testUtils.h>
 #include <TH1F.h>
+#include <cstdlib>
 
 using namespace std;
 using namespace o2::quality_control::core;
 
+// A QC-specific CCDB instance: ali-qcdb-test by default. It holds different
+// objects from ccdb-test -- see the TODO in testTimekeeper.cxx -- so this is
+// deliberately NOT ALICEO2_CCDB_HOST. ALICEO2_QCDB_HOST lets a network-isolated
+// build container reach it through a broker instead; unset, behaviour is
+// unchanged.
+const std::string QCDB_ENDPOINT = [] {
+  const char* host = std::getenv("ALICEO2_QCDB_HOST");
+  return std::string((host && *host) ? host : "ali-qcdb-test.cern.ch:8083");
+}();
+
 namespace o2::quality_control::repository
 {
 
@@ -68,7 +79,7 @@ BOOST_AUTO_TEST_CASE(db_ccdb_listing)
   auto* ccdb = dynamic_cast<CcdbDatabase*>(database3.get());
   BOOST_CHECK(ccdb);
 
-  ccdb->connect("ali-qcdb-test.cern.ch:8083", "", "", "");
+  ccdb->connect(QCDB_ENDPOINT, "", "", "");
 
   // prepare stuff in the db
   string prefixPath = "qc/TST/MO/";
diff --git a/Framework/test/testTaskInterface.cxx b/Framework/test/testTaskInterface.cxx
index e955ecf29c..89b65e3eda 100644
--- a/Framework/test/testTaskInterface.cxx
+++ b/Framework/test/testTaskInterface.cxx
@@ -52,6 +52,7 @@ o2::framework::ConfigParamRegistry createDummyRegistry()
 #include <Framework/ConfigParamRegistry.h>
 #include <Framework/ServiceRegistry.h>
 #include <catch_amalgamated.hpp>
+#include <cstdlib>
 
 using namespace o2::quality_control;
 using namespace std;
@@ -62,6 +63,16 @@ namespace o2::quality_control
 
 using namespace core;
 
+// A QC-specific CCDB instance: ali-qcdb-test by default. It holds different
+// objects from ccdb-test -- see the TODO in testTimekeeper.cxx -- so this is
+// deliberately NOT ALICEO2_CCDB_HOST. ALICEO2_QCDB_HOST lets a network-isolated
+// build container reach it through a broker instead; unset, behaviour is
+// unchanged.
+const std::string QCDB_ENDPOINT = [] {
+  const char* host = std::getenv("ALICEO2_QCDB_HOST");
+  return std::string((host && *host) ? host : "ali-qcdb-test.cern.ch:8083");
+}();
+
 namespace test
 {
 class TestTask : public TaskInterface
@@ -201,14 +212,14 @@ TEST_CASE("retrieveCondition")
   bad.addBadChannel(3, o2::emcal::BadChannelMap::MaskType_t::DEAD_CELL);
   std::map<std::string, std::string> meta;
   o2::ccdb::CcdbApi api;
-  api.init("ali-qcdb-test.cern.ch:8083");
+  api.init(QCDB_ENDPOINT);
   api.storeAsTFileAny<o2::emcal::BadChannelMap>(&bad, "qc/TST/conditions", meta);
 
   // retrieve it
   TaskRunnerConfig taskConfig;
   auto* objectsManager = new ObjectsManager(taskConfig.name, taskConfig.className, taskConfig.detectorName, 0);
   test::TestTask testTask(objectsManager);
-  testTask.setCcdbUrl("ali-qcdb-test.cern.ch:8083");
+  testTask.setCcdbUrl(QCDB_ENDPOINT);
   o2::emcal::BadChannelMap* bcm = testTask.testRetrieveCondition();
   CHECK(bcm->getChannelStatus(1) == o2::emcal::BadChannelMap::MaskType_t::GOOD_CELL);
   CHECK(bcm->getChannelStatus(3) == o2::emcal::BadChannelMap::MaskType_t::DEAD_CELL);
diff --git a/Framework/test/testTimekeeper.cxx b/Framework/test/testTimekeeper.cxx
index 45b40bae9c..ef8f46df60 100644
--- a/Framework/test/testTimekeeper.cxx
+++ b/Framework/test/testTimekeeper.cxx
@@ -22,10 +22,21 @@
 #include <CommonUtils/ConfigurableParam.h>
 
 #include <catch_amalgamated.hpp>
+#include <cstdlib>
 
 using namespace o2::quality_control::core;
 using namespace o2::framework;
 
+// A QC-specific CCDB instance: ali-qcdb-test by default. It holds different
+// objects from ccdb-test -- see the TODO in testTimekeeper.cxx -- so this is
+// deliberately NOT ALICEO2_CCDB_HOST. ALICEO2_QCDB_HOST lets a network-isolated
+// build container reach it through a broker instead; unset, behaviour is
+// unchanged.
+const std::string QCDB_ENDPOINT = [] {
+  const char* host = std::getenv("ALICEO2_QCDB_HOST");
+  return std::string((host && *host) ? host : "ali-qcdb-test.cern.ch:8083");
+}();
+
 TEST_CASE("timekeeper_synchronous")
 {
   SECTION("defaults")
@@ -310,7 +321,7 @@ TEST_CASE("timekeeper_asynchronous")
   {
     auto tk = std::make_shared<TimekeeperAsynchronous>();
 
-    o2::conf::ConfigurableParam::updateFromString("NameConf.mCCDBServer=http://ali-qcdb-test.cern.ch:8083");
+    o2::conf::ConfigurableParam::updateFromString("NameConf.mCCDBServer=http://" + QCDB_ENDPOINT);
 
     // CCDB RCT first
     // TODO reactivate but we need the info in ali-qcdb-test (it is only in ccdb-test)
diff --git a/Framework/test/testTrendingTask.cxx b/Framework/test/testTrendingTask.cxx
index 0bb1ae38b6..0c3872483d 100644
--- a/Framework/test/testTrendingTask.cxx
+++ b/Framework/test/testTrendingTask.cxx
@@ -30,13 +30,22 @@
 #include <functional>
 
 #include <catch_amalgamated.hpp>
+#include <cstdlib>
 
 using namespace o2::quality_control::core;
 using namespace o2::quality_control::postprocessing;
 using namespace o2::quality_control::repository;
 using namespace o2::framework;
 
-const std::string CCDB_ENDPOINT = "ali-qcdb-test.cern.ch:8083";
+// A QC-specific CCDB instance: ali-qcdb-test by default. It holds different
+// objects from ccdb-test -- see the TODO in testTimekeeper.cxx -- so this is
+// deliberately NOT ALICEO2_CCDB_HOST. ALICEO2_QCDB_HOST lets a network-isolated
+// build container reach it through a broker instead; unset, behaviour is
+// unchanged.
+const std::string QCDB_ENDPOINT = [] {
+  const char* host = std::getenv("ALICEO2_QCDB_HOST");
+  return std::string((host && *host) ? host : "ali-qcdb-test.cern.ch:8083");
+}();
 
 struct CleanupAtDestruction {
  public:
@@ -86,7 +95,8 @@ TEST_CASE("test_trending_task")
     "config": {
       "database": {
         "implementation": "CCDB",
-        "host": "ali-qcdb-test.cern.ch:8083"
+        "host": ")json"
+     << QCDB_ENDPOINT << R"json("
       },
       "Activity": {},
       "monitoring": {
@@ -105,7 +115,7 @@ TEST_CASE("test_trending_task")
           {
             "type": "repository",
             "path": "TST/MO/)json" +
-          taskName + R"json(",
+                           taskName + R"json(",
             "name": "testHistoTrending",
             "reductorName": "o2::quality_control_modules::common::TH1Reductor",
             "reductorParameters": {
@@ -121,7 +131,7 @@ TEST_CASE("test_trending_task")
             "type": "repository-quality",
             "path": "TST/QO",
             "names": [ ")json" +
-          checkName + R"json(" ],
+                           checkName + R"json(" ],
             "reductorName": "o2::quality_control_modules::common::QualityReductor",
             "moduleName": "QcCommon"
           }
@@ -140,7 +150,7 @@ TEST_CASE("test_trending_task")
             "name": "quality_histogram",
             "title": "Histogram of qualities",
             "varexp": ")json" +
-          checkName + R"json(.level",
+                           checkName + R"json(.level",
             "selection": "",
             "option": ""
           }
@@ -157,7 +167,7 @@ TEST_CASE("test_trending_task")
 
   // clean
   std::shared_ptr<DatabaseInterface> repository = DatabaseFactory::create("CCDB");
-  repository->connect(CCDB_ENDPOINT, "", "", "");
+  repository->connect(QCDB_ENDPOINT, "", "", "");
   repository->truncate("qc/TST/MO/" + taskName, "*");
   repository->truncate("qc/TST/QO", checkName);
 
diff --git a/Framework/test/testTriggerHelpers.cxx b/Framework/test/testTriggerHelpers.cxx
index 35eb4ebb78..15ad755491 100644
--- a/Framework/test/testTriggerHelpers.cxx
+++ b/Framework/test/testTriggerHelpers.cxx
@@ -17,9 +17,19 @@
 #include "QualityControl/TriggerHelpers.h"
 #include "QualityControl/PostProcessingConfig.h"
 #include <catch_amalgamated.hpp>
+#include <cstdlib>
 
 using namespace o2::quality_control::postprocessing;
-const std::string CCDB_ENDPOINT = "ali-qcdb-test.cern.ch:8083";
+
+// A QC-specific CCDB instance: ali-qcdb-test by default. It holds different
+// objects from ccdb-test -- see the TODO in testTimekeeper.cxx -- so this is
+// deliberately NOT ALICEO2_CCDB_HOST. ALICEO2_QCDB_HOST lets a network-isolated
+// build container reach it through a broker instead; unset, behaviour is
+// unchanged.
+const std::string QCDB_ENDPOINT = [] {
+  const char* host = std::getenv("ALICEO2_QCDB_HOST");
+  return std::string((host && *host) ? host : "ali-qcdb-test.cern.ch:8083");
+}();
 
 TEST_CASE("test_factory")
 {
@@ -63,8 +73,8 @@ TEST_CASE("test_factory")
 
   // generating new object trigger
   PostProcessingConfig configWithDBs;
-  configWithDBs.repository["host"] = CCDB_ENDPOINT;
-  configWithDBs.ccdbUrl = CCDB_ENDPOINT;
+  configWithDBs.repository["host"] = QCDB_ENDPOINT;
+  configWithDBs.ccdbUrl = QCDB_ENDPOINT;
   CHECK_NOTHROW(trigger_helpers::triggerFactory("newobject:qcdb:qc/asdf/vcxz", configWithDBs));
   CHECK_NOTHROW(trigger_helpers::triggerFactory("newobject:ccdb:qc/asdf/vcxz", configWithDBs));
   CHECK_NOTHROW(trigger_helpers::triggerFactory("newobject:QCDB:qc/asdf/vcxz", configWithDBs));
diff --git a/Framework/test/testUserCodeInterface.cxx b/Framework/test/testUserCodeInterface.cxx
index 4835986571..7aed577c89 100644
--- a/Framework/test/testUserCodeInterface.cxx
+++ b/Framework/test/testUserCodeInterface.cxx
@@ -28,11 +28,22 @@
 
 #include <QualityControl/CcdbDatabase.h>
 #include <QualityControl/CustomParameters.h>
+#include <cstdlib>
 
 using namespace std;
 using namespace o2::quality_control::repository;
 using namespace o2::quality_control::core;
 
+// A QC-specific CCDB instance: ali-qcdb-test by default. It holds different
+// objects from ccdb-test -- see the TODO in testTimekeeper.cxx -- so this is
+// deliberately NOT ALICEO2_CCDB_HOST. ALICEO2_QCDB_HOST lets a network-isolated
+// build container reach it through a broker instead; unset, behaviour is
+// unchanged.
+const std::string QCDB_ENDPOINT = [] {
+  const char* host = std::getenv("ALICEO2_QCDB_HOST");
+  return std::string((host && *host) ? host : "ali-qcdb-test.cern.ch:8083");
+}();
+
 namespace o2::quality_control
 {
 
@@ -65,7 +76,7 @@ struct MyGlobalFixture {
   void teardown()
   {
     auto backend = std::make_unique<CcdbDatabase>();
-    backend->connect("ali-qcdb-test.cern.ch:8083", "", "", "");
+    backend->connect(QCDB_ENDPOINT, "", "", "");
     backend->truncate("qc/TST/MO/Test/pid" + std::to_string(getpid()), "*");
   }
 };
@@ -82,7 +93,7 @@ BOOST_AUTO_TEST_CASE(test_invoke_all_methods)
   auto taskName = "Test/pid" + pid;
   shared_ptr<MonitorObject> mo1 = make_shared<MonitorObject>(h1, taskName, "task", "TST");
   auto backend = std::make_unique<CcdbDatabase>();
-  backend->connect("ali-qcdb-test.cern.ch:8083", "", "", "");
+  backend->connect(QCDB_ENDPOINT, "", "", "");
   backend->storeMO(mo1);
 
   // setting custom parameters should configure
@@ -92,7 +103,7 @@ BOOST_AUTO_TEST_CASE(test_invoke_all_methods)
   BOOST_CHECK_EQUAL(testInterface.configured, true);
   BOOST_CHECK_EQUAL(testInterface.get("test"), "asdf");
 
-  testInterface.setCcdbUrl("ali-qcdb-test.cern.ch:8083");
+  testInterface.setCcdbUrl(QCDB_ENDPOINT);
   auto obj = testInterface.retrieveConditionAny<TObject>("qc/TST/MO/" + taskName + "/asdf");
   BOOST_CHECK_NE(obj, nullptr);
 }