diff --git a/CondCore/DBOutputService/interface/OnlineDBOutputService.h b/CondCore/DBOutputService/interface/OnlineDBOutputService.h
index e72dbed396b21..b65829cd42685 100644
--- a/CondCore/DBOutputService/interface/OnlineDBOutputService.h
+++ b/CondCore/DBOutputService/interface/OnlineDBOutputService.h
@@ -84,6 +84,7 @@ namespace cond {
       std::string m_omsServiceUrl;
       std::string m_lastLumiFile;
       std::string m_preLoadConnectionString;
+      std::string m_frontierKey;
       bool m_debug;
 
     };  //OnlineDBOutputService
diff --git a/CondCore/DBOutputService/src/OnlineDBOutputService.cc b/CondCore/DBOutputService/src/OnlineDBOutputService.cc
index babbf7d2a7731..0136c1fc6748b 100644
--- a/CondCore/DBOutputService/src/OnlineDBOutputService.cc
+++ b/CondCore/DBOutputService/src/OnlineDBOutputService.cc
@@ -84,10 +84,18 @@ cond::service::OnlineDBOutputService::OnlineDBOutputService(const edm::Parameter
       m_latencyInLumisections(iConfig.getUntrackedParameter<unsigned int>("latency", 1)),
       m_omsServiceUrl(iConfig.getUntrackedParameter<std::string>("omsServiceUrl", "")),
       m_preLoadConnectionString(iConfig.getUntrackedParameter<std::string>("preLoadConnectionString", "")),
+      m_frontierKey(""),
       m_debug(iConfig.getUntrackedParameter<bool>("debugLogging", false)) {
   if (m_omsServiceUrl.empty()) {
     m_lastLumiFile = iConfig.getUntrackedParameter<std::string>("lastLumiFile", "");
   }
+  std::string frontierKeyFilePath(iConfig.getUntrackedParameter<std::string>("frontierKeyFilePath", ""));
+  if (!frontierKeyFilePath.empty()) {
+    std::ifstream frontierKeyFile(frontierKeyFilePath);
+    if (!frontierKeyFile)
+      throw Exception(std::string("Can't access frontierKey file ") + frontierKeyFilePath);
+    frontierKeyFile >> m_frontierKey;
+  }
 }
 
 cond::service::OnlineDBOutputService::~OnlineDBOutputService() {}
@@ -124,5 +132,10 @@ cond::Iov_t cond::service::OnlineDBOutputService::preLoadIov(const std::string&
 }
 
 cond::persistency::Session cond::service::OnlineDBOutputService::getReadOnlyCache(cond::Time_t targetTime) {
-  return PoolDBOutputService::newReadOnlySession(m_preLoadConnectionString, std::to_string(targetTime));
+  std::stringstream transId;
+  transId << targetTime;
+  if (!m_frontierKey.empty()) {
+    transId << "_" << m_frontierKey;
+  }
+  return PoolDBOutputService::newReadOnlySession(m_preLoadConnectionString, transId.str());
 }
diff --git a/CondCore/DBOutputService/test/python/testLumiBasedUpdateAnalyzer_oracle.cfg.py b/CondCore/DBOutputService/test/python/testLumiBasedUpdateAnalyzer_oracle.cfg.py
index 5276120555a44..586a1cc8c1498 100644
--- a/CondCore/DBOutputService/test/python/testLumiBasedUpdateAnalyzer_oracle.cfg.py
+++ b/CondCore/DBOutputService/test/python/testLumiBasedUpdateAnalyzer_oracle.cfg.py
@@ -32,12 +32,12 @@
         messageLevel = cms.untracked.int32(1),
         authenticationPath = cms.untracked.string('.')
     ),
-    #timetype = cms.untracked.string('runnumber'),
     jobName = cms.untracked.string("TestLumiBasedUpdate"),
     connect = cms.string('oracle://cms_orcoff_prep/CMS_CONDITIONS'),
     preLoadConnectionString = cms.untracked.string('frontier://FrontierPrep/CMS_CONDITIONS'),
     runNumber = cms.untracked.uint64(options.runNumber),
     #lastLumiFile = cms.untracked.string('last_lumi.txt'),
+    #frontierKeyFilePath = cms.untracked.string('frontier.key'),
     writeTransactionDelay = cms.untracked.uint32(options.transDelay),
     autoCommit = cms.untracked.bool(True),
     saveLogsOnDB = cms.untracked.bool(True),
diff --git a/CondCore/ESSources/plugins/CondDBESSource.cc b/CondCore/ESSources/plugins/CondDBESSource.cc
index e54bfacd7c356..c6968fdee0217 100644
--- a/CondCore/ESSources/plugins/CondDBESSource.cc
+++ b/CondCore/ESSources/plugins/CondDBESSource.cc
@@ -98,6 +98,7 @@ namespace {
 CondDBESSource::CondDBESSource(const edm::ParameterSet& iConfig)
     : m_connection(),
       m_connectionString(""),
+      m_frontierKey(""),
       m_lastRun(0),   // for the stat
       m_lastLumi(0),  // for the stat
       m_policy(NOREFRESH),
@@ -139,6 +140,11 @@ CondDBESSource::CondDBESSource(const edm::ParameterSet& iConfig)
   } else if (iConfig.exists("connect"))  // default connection string
     m_connectionString = iConfig.getParameter<std::string>("connect");
 
+  // frontier key
+  if (iConfig.exists("frontierKey")) {
+    m_frontierKey = iConfig.getParameter<std::string>("frontierKey");
+  }
+
   // snapshot
   boost::posix_time::ptime snapshotTime;
   if (iConfig.exists("snapshotTime")) {
@@ -453,8 +459,10 @@ void CondDBESSource::setIntervalFor(const EventSetupRecordKey& iKey,
             << "Checking if the session must be closed and re-opened for getting correct conditions"
             << "; from CondDBESSource::setIntervalFor";
         std::stringstream transId;
-        //transId << "long" << m_lastRun;
         transId << lastTime;
+        if (!m_frontierKey.empty()) {
+          transId << "_" << m_frontierKey;
+        }
         std::string connStr = m_connectionString;
         std::pair<std::string, std::string> tagParams = cond::persistency::parseTag(tcIter->second.tagName());
         if (!tagParams.second.empty())
diff --git a/CondCore/ESSources/plugins/CondDBESSource.h b/CondCore/ESSources/plugins/CondDBESSource.h
index 7c6673e5421da..8635688c28bfc 100644
--- a/CondCore/ESSources/plugins/CondDBESSource.h
+++ b/CondCore/ESSources/plugins/CondDBESSource.h
@@ -110,6 +110,7 @@ class CondDBESSource : public edm::eventsetup::DataProxyProvider, public edm::Ev
 
   cond::persistency::ConnectionPool m_connection;
   std::string m_connectionString;
+  std::string m_frontierKey;
 
   // Container of DataProxy, implemented as multi-map keyed by records
   ProxyMap m_proxies;
diff --git a/CondCore/ESSources/test/python/loadall_from_one_record_empty_source_cfg.py b/CondCore/ESSources/test/python/loadall_from_one_record_empty_source_cfg.py
index f8674b986b057..efc00d3a582be 100644
--- a/CondCore/ESSources/test/python/loadall_from_one_record_empty_source_cfg.py
+++ b/CondCore/ESSources/test/python/loadall_from_one_record_empty_source_cfg.py
@@ -107,6 +107,7 @@
                                   DBParameters = CondDBParameters,
                                   connect = cms.string( options.connectionString ),
                                   snapshotTime = cms.string( options.snapshotTime ),
+                                  frontierKey = cms.string('abcdefghijklmnopqrstuvwxyz0123456789'),
                                   toGet = cms.VPSet(cms.PSet(
                                       record = cms.string('BeamSpotObjectsRcd'),
                                       tag = cms.string( options.tag ),