diff --git a/client.c b/client.c
index 3c605c1..774343e 100644
--- a/client.c
+++ b/client.c
@@ -1105,7 +1105,7 @@ process_cmd_add_server_or_peer(CMD_Request *msg, char *line)
       msg->data.ntp_source.asymmetry = UTI_FloatHostToNetwork(data.params.asymmetry);
       msg->data.ntp_source.offset = UTI_FloatHostToNetwork(data.params.offset);
       msg->data.ntp_source.flags = htonl(
-          (data.params.online ? REQ_ADDSRC_ONLINE : 0) |
+          (data.params.connectivity == SRC_ONLINE ? REQ_ADDSRC_ONLINE : 0) |
           (data.params.auto_offline ? REQ_ADDSRC_AUTOOFFLINE : 0) |
           (data.params.iburst ? REQ_ADDSRC_IBURST : 0) |
           (data.params.interleaved ? REQ_ADDSRC_INTERLEAVED : 0) |
diff --git a/cmdmon.c b/cmdmon.c
index 3bd8d91..01cf49e 100644
--- a/cmdmon.c
+++ b/cmdmon.c
@@ -424,7 +424,7 @@ handle_online(CMD_Request *rx_message, CMD_Reply *tx_message)
 
   UTI_IPNetworkToHost(&rx_message->data.online.mask, &mask);
   UTI_IPNetworkToHost(&rx_message->data.online.address, &address);
-  if (!NSR_TakeSourcesOnline(&mask, &address))
+  if (!NSR_SetConnectivity(&mask, &address, SRC_ONLINE))
     tx_message->status = htons(STT_NOSUCHSOURCE);
 }
 
@@ -437,7 +437,7 @@ handle_offline(CMD_Request *rx_message, CMD_Reply *tx_message)
 
   UTI_IPNetworkToHost(&rx_message->data.offline.mask, &mask);
   UTI_IPNetworkToHost(&rx_message->data.offline.address, &address);
-  if (!NSR_TakeSourcesOffline(&mask, &address))
+  if (!NSR_SetConnectivity(&mask, &address, SRC_OFFLINE))
     tx_message->status = htons(STT_NOSUCHSOURCE);
 }
 
@@ -797,7 +797,8 @@ handle_add_source(NTP_Source_Type type, CMD_Request *rx_message, CMD_Reply *tx_m
   params.asymmetry = UTI_FloatNetworkToHost(rx_message->data.ntp_source.asymmetry);
   params.offset = UTI_FloatNetworkToHost(rx_message->data.ntp_source.offset);
 
-  params.online  = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_ONLINE ? 1 : 0;
+  params.connectivity = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_ONLINE ?
+                        SRC_ONLINE : SRC_OFFLINE;
   params.auto_offline = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_AUTOOFFLINE ? 1 : 0;
   params.iburst = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_IBURST ? 1 : 0;
   params.interleaved = ntohl(rx_message->data.ntp_source.flags) & REQ_ADDSRC_INTERLEAVED ? 1 : 0;
diff --git a/cmdparse.c b/cmdparse.c
index a228530..5f9a4e0 100644
--- a/cmdparse.c
+++ b/cmdparse.c
@@ -48,7 +48,7 @@ CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src)
   src->port = SRC_DEFAULT_PORT;
   src->params.minpoll = SRC_DEFAULT_MINPOLL;
   src->params.maxpoll = SRC_DEFAULT_MAXPOLL;
-  src->params.online = 1;
+  src->params.connectivity = SRC_ONLINE;
   src->params.auto_offline = 0;
   src->params.presend_minpoll = SRC_DEFAULT_PRESEND_MINPOLL;
   src->params.burst = 0;
@@ -90,7 +90,7 @@ CPS_ParseNTPSourceAdd(char *line, CPS_NTP_Source *src)
     } else if (!strcasecmp(cmd, "iburst")) {
       src->params.iburst = 1;
     } else if (!strcasecmp(cmd, "offline")) {
-      src->params.online = 0;
+      src->params.connectivity = SRC_OFFLINE;
     } else if (!strcasecmp(cmd, "noselect")) {
       src->params.sel_options |= SRC_SELECT_NOSELECT;
     } else if (!strcasecmp(cmd, "prefer")) {
diff --git a/conf.c b/conf.c
index 3859d74..ef6db08 100644
--- a/conf.c
+++ b/conf.c
@@ -1411,7 +1411,7 @@ CNF_AddInitSources(void)
     ntp_addr.ip_addr = *(IPAddr *)ARR_GetElement(init_sources, i);
     ntp_addr.port = cps_source.port;
     cps_source.params.iburst = 1;
-    cps_source.params.online = 0;
+    cps_source.params.connectivity = SRC_OFFLINE;
 
     NSR_AddSource(&ntp_addr, NTP_SERVER, &cps_source.params);
   }
diff --git a/ntp_core.c b/ntp_core.c
index c82d792..45956e7 100644
--- a/ntp_core.c
+++ b/ntp_core.c
@@ -603,7 +603,7 @@ NCR_GetInstance(NTP_Remote_Address *remote_addr, NTP_Source_Type type, SourcePar
   result->rx_timeout_id = 0;
   result->tx_timeout_id = 0;
   result->tx_suspended = 1;
-  result->opmode = params->online ? MD_ONLINE : MD_OFFLINE;
+  result->opmode = params->connectivity == SRC_ONLINE ? MD_ONLINE : MD_OFFLINE;
   result->local_poll = result->minpoll;
   result->poll_score = 0.0;
   zero_local_timestamp(&result->local_tx);
@@ -1143,7 +1143,7 @@ transmit_timeout(void *arg)
 
   /* With auto_offline take the source offline on 2nd missed reply */
   if (inst->auto_offline && inst->tx_count >= 2)
-    NCR_TakeSourceOffline(inst);
+    NCR_SetConnectivity(inst, SRC_OFFLINE);
 
   if (inst->opmode == MD_OFFLINE) {
     return;
@@ -2275,52 +2275,60 @@ NCR_SlewTimes(NCR_Instance inst, struct timespec *when, double dfreq, double dof
 /* ================================================== */
 
 void
-NCR_TakeSourceOnline(NCR_Instance inst)
+NCR_SetConnectivity(NCR_Instance inst, SRC_Connectivity connectivity)
 {
-  switch (inst->opmode) {
-    case MD_ONLINE:
-      /* Nothing to do */
+  char *s;
+
+  s = UTI_IPToString(&inst->remote_addr.ip_addr);
+
+  switch (connectivity) {
+    case SRC_ONLINE:
+      switch (inst->opmode) {
+        case MD_ONLINE:
+          /* Nothing to do */
+          break;
+        case MD_OFFLINE:
+          LOG(LOGS_INFO, "Source %s online", s);
+          inst->opmode = MD_ONLINE;
+          NCR_ResetInstance(inst);
+          start_initial_timeout(inst);
+          break;
+        case MD_BURST_WAS_ONLINE:
+          /* Will revert */
+          break;
+        case MD_BURST_WAS_OFFLINE:
+          inst->opmode = MD_BURST_WAS_ONLINE;
+          LOG(LOGS_INFO, "Source %s online", s);
+          break;
+        default:
+          assert(0);
+      }
       break;
-    case MD_OFFLINE:
-      LOG(LOGS_INFO, "Source %s online", UTI_IPToString(&inst->remote_addr.ip_addr));
-      inst->opmode = MD_ONLINE;
-      NCR_ResetInstance(inst);
-      start_initial_timeout(inst);
-      break;
-    case MD_BURST_WAS_ONLINE:
-      /* Will revert */
-      break;
-    case MD_BURST_WAS_OFFLINE:
-      inst->opmode = MD_BURST_WAS_ONLINE;
-      LOG(LOGS_INFO, "Source %s online", UTI_IPToString(&inst->remote_addr.ip_addr));
+    case SRC_OFFLINE:
+      switch (inst->opmode) {
+        case MD_ONLINE:
+          LOG(LOGS_INFO, "Source %s offline", s);
+          take_offline(inst);
+          break;
+        case MD_OFFLINE:
+          break;
+        case MD_BURST_WAS_ONLINE:
+          inst->opmode = MD_BURST_WAS_OFFLINE;
+          LOG(LOGS_INFO, "Source %s offline", s);
+          break;
+        case MD_BURST_WAS_OFFLINE:
+          break;
+        default:
+          assert(0);
+      }
       break;
+    default:
+      assert(0);
   }
 }
 
 /* ================================================== */
 
-void
-NCR_TakeSourceOffline(NCR_Instance inst)
-{
-  switch (inst->opmode) {
-    case MD_ONLINE:
-      LOG(LOGS_INFO, "Source %s offline", UTI_IPToString(&inst->remote_addr.ip_addr));
-      take_offline(inst);
-      break;
-    case MD_OFFLINE:
-      break;
-    case MD_BURST_WAS_ONLINE:
-      inst->opmode = MD_BURST_WAS_OFFLINE;
-      LOG(LOGS_INFO, "Source %s offline", UTI_IPToString(&inst->remote_addr.ip_addr));
-      break;
-    case MD_BURST_WAS_OFFLINE:
-      break;
-  }
-
-}
-
-/* ================================================== */
-
 void
 NCR_ModifyMinpoll(NCR_Instance inst, int new_minpoll)
 {
diff --git a/ntp_core.h b/ntp_core.h
index f788d68..522d59b 100644
--- a/ntp_core.h
+++ b/ntp_core.h
@@ -99,12 +99,9 @@ extern void NCR_ProcessTxUnknown(NTP_Remote_Address *remote_addr, NTP_Local_Addr
 /* Slew receive and transmit times in instance records */
 extern void NCR_SlewTimes(NCR_Instance inst, struct timespec *when, double dfreq, double doffset);
 
-/* Take a particular source online (i.e. start sampling it) */
-extern void NCR_TakeSourceOnline(NCR_Instance inst);
-
-/* Take a particular source offline (i.e. stop sampling it, without
-   marking it unreachable in the source selection stuff) */
-extern void NCR_TakeSourceOffline(NCR_Instance inst);
+/* Take a particular source online (i.e. start sampling it) or offline
+   (i.e. stop sampling it) */
+extern void NCR_SetConnectivity(NCR_Instance inst, SRC_Connectivity connectivity);
 
 extern void NCR_ModifyMinpoll(NCR_Instance inst, int new_minpoll);
 
diff --git a/ntp_sources.c b/ntp_sources.c
index e7fb60f..fa21654 100644
--- a/ntp_sources.c
+++ b/ntp_sources.c
@@ -860,48 +860,14 @@ slew_sources(struct timespec *raw,
 /* ================================================== */
 
 int
-NSR_TakeSourcesOnline(IPAddr *mask, IPAddr *address)
-{
-  SourceRecord *record;
-  unsigned int i;
-  int any;
-
-  NSR_ResolveSources();
-
-  any = 0;
-  for (i = 0; i < ARR_GetSize(records); i++) {
-    record = get_record(i);
-    if (record->remote_addr) {
-      if (address->family == IPADDR_UNSPEC ||
-          !UTI_CompareIPs(&record->remote_addr->ip_addr, address, mask)) {
-        any = 1;
-        NCR_TakeSourceOnline(record->data);
-      }
-    }
-  }
-
-  if (address->family == IPADDR_UNSPEC) {
-    struct UnresolvedSource *us;
-
-    for (us = unresolved_sources; us; us = us->next) {
-      if (us->replacement)
-        continue;
-      any = 1;
-      us->new_source.params.online = 1;
-    }
-  }
-
-  return any;
-}
-
-/* ================================================== */
-
-int
-NSR_TakeSourcesOffline(IPAddr *mask, IPAddr *address)
+NSR_SetConnectivity(IPAddr *mask, IPAddr *address, SRC_Connectivity connectivity)
 {
   SourceRecord *record, *syncpeer;
   unsigned int i, any;
 
+  if (connectivity != SRC_OFFLINE)
+    NSR_ResolveSources();
+
   any = 0;
   syncpeer = NULL;
   for (i = 0; i < ARR_GetSize(records); i++) {
@@ -914,15 +880,14 @@ NSR_TakeSourcesOffline(IPAddr *mask, IPAddr *address)
           syncpeer = record;
           continue;
         }
-        NCR_TakeSourceOffline(record->data);
+        NCR_SetConnectivity(record->data, connectivity);
       }
     }
   }
 
-  /* Take sync peer offline as last to avoid reference switching */
-  if (syncpeer) {
-    NCR_TakeSourceOffline(syncpeer->data);
-  }
+  /* Set the sync peer last to avoid unnecessary reference switching */
+  if (syncpeer)
+    NCR_SetConnectivity(syncpeer->data, connectivity);
 
   if (address->family == IPADDR_UNSPEC) {
     struct UnresolvedSource *us;
@@ -931,7 +896,7 @@ NSR_TakeSourcesOffline(IPAddr *mask, IPAddr *address)
       if (us->replacement)
         continue;
       any = 1;
-      us->new_source.params.online = 0;
+      us->new_source.params.connectivity = connectivity;
     }
   }
 
diff --git a/ntp_sources.h b/ntp_sources.h
index 23e9612..16b62be 100644
--- a/ntp_sources.h
+++ b/ntp_sources.h
@@ -102,14 +102,9 @@ extern void NSR_Initialise(void);
 extern void NSR_Finalise(void);
 
 /* This routine is used to indicate that sources whose IP addresses
-   match a particular subnet should be set online again.  Returns a
-   flag indicating whether any hosts matched the address */
-extern int NSR_TakeSourcesOnline(IPAddr *mask, IPAddr *address);
-
-/* This routine is used to indicate that sources whose IP addresses
-   match a particular subnet should be set offline.  Returns a flag
-   indicating whether any hosts matched the address */
-extern int NSR_TakeSourcesOffline(IPAddr *mask, IPAddr *address);
+   match a particular subnet should be set online or offline.  It returns
+   a flag indicating whether any hosts matched the address. */
+extern int NSR_SetConnectivity(IPAddr *mask, IPAddr *address, SRC_Connectivity connectivity);
 
 extern int NSR_ModifyMinpoll(IPAddr *address, int new_minpoll);
 
diff --git a/srcparams.h b/srcparams.h
index 7a73bad..48fa19c 100644
--- a/srcparams.h
+++ b/srcparams.h
@@ -29,10 +29,15 @@
 
 #include "sources.h"
 
+typedef enum {
+  SRC_OFFLINE,
+  SRC_ONLINE,
+} SRC_Connectivity;
+
 typedef struct {
   int minpoll;
   int maxpoll;
-  int online;
+  SRC_Connectivity connectivity;
   int auto_offline;
   int presend_minpoll;
   int burst;
diff --git a/stubs.c b/stubs.c
index eac81c0..00b07ac 100644
--- a/stubs.c
+++ b/stubs.c
@@ -254,13 +254,7 @@ NSR_GetLocalRefid(IPAddr *address)
 }
 
 int
-NSR_TakeSourcesOnline(IPAddr *mask, IPAddr *address)
-{
-  return 0;
-}
-
-int
-NSR_TakeSourcesOffline(IPAddr *mask, IPAddr *address)
+NSR_SetConnectivity(IPAddr *mask, IPAddr *address, SRC_Connectivity connectivity)
 {
   return 0;
 }