diff --git a/src/lib/dhcpsrv/pool.cc b/src/lib/dhcpsrv/pool.cc
index 9323ad9f6b..4499df2018 100644
--- a/src/lib/dhcpsrv/pool.cc
+++ b/src/lib/dhcpsrv/pool.cc
@@ -20,9 +20,9 @@ namespace dhcp {
 
 Pool::Pool(Lease::Type type, const isc::asiolink::IOAddress& first,
            const isc::asiolink::IOAddress& last)
-    :id_(getNextID()), first_(first), last_(last), type_(type),
-     capacity_(0), cfg_option_(new CfgOption()), client_class_(""),
-     permutation_() {
+    : id_(getNextID()), first_(first), last_(last), type_(type),
+      capacity_(0), cfg_option_(new CfgOption()), client_class_(""),
+      permutation_() {
 }
 
 bool Pool::inRange(const isc::asiolink::IOAddress& addr) const {
@@ -47,7 +47,7 @@ Pool::toText() const {
 
 Pool4::Pool4(const isc::asiolink::IOAddress& first,
              const isc::asiolink::IOAddress& last)
-:Pool(Lease::TYPE_V4, first, last) {
+    : Pool(Lease::TYPE_V4, first, last) {
     // check if specified address boundaries are sane
     if (!first.isV4() || !last.isV4()) {
         isc_throw(BadValue, "Invalid Pool4 address boundaries: not IPv4");
@@ -64,8 +64,8 @@ Pool4::Pool4(const isc::asiolink::IOAddress& first,
     capacity_ = addrsInRange(first, last);
 }
 
-Pool4::Pool4( const isc::asiolink::IOAddress& prefix, uint8_t prefix_len)
-:Pool(Lease::TYPE_V4, prefix, IOAddress("0.0.0.0")) {
+Pool4::Pool4(const isc::asiolink::IOAddress& prefix, uint8_t prefix_len)
+    : Pool(Lease::TYPE_V4, prefix, IOAddress("0.0.0.0")) {
 
     // check if the prefix is sane
     if (!prefix.isV4()) {
@@ -77,6 +77,13 @@ Pool4::Pool4( const isc::asiolink::IOAddress& prefix, uint8_t prefix_len)
         isc_throw(BadValue, "Invalid prefix length");
     }
 
+    IOAddress first_address = firstAddrInPrefix(prefix, prefix_len);
+    if (first_address != prefix) {
+        isc_throw(BadValue, "Invalid Pool4 address boundaries: " << prefix
+                  << " is not the first address in prefix: " << first_address
+                  << "/" << static_cast<uint32_t>(prefix_len));
+    }
+
     // Let's now calculate the last address in defined pool
     last_ = lastAddrInPrefix(prefix, prefix_len);
 
@@ -160,8 +167,8 @@ Pool6::Pool6(Lease::Type type, const isc::asiolink::IOAddress& first,
         isc_throw(BadValue, "Invalid Pool6 address boundaries: not IPv6");
     }
 
-    if ( (type != Lease::TYPE_NA) && (type != Lease::TYPE_TA) &&
-         (type != Lease::TYPE_PD)) {
+    if ((type != Lease::TYPE_NA) && (type != Lease::TYPE_TA) &&
+        (type != Lease::TYPE_PD)) {
         isc_throw(BadValue, "Invalid Pool6 type: " << static_cast<int>(type)
                   << ", must be TYPE_IA, TYPE_TA or TYPE_PD");
     }
@@ -241,7 +248,7 @@ Pool6::Pool6(const asiolink::IOAddress& prefix, const uint8_t prefix_len,
         if (excluded_prefix_len <= prefix_len_) {
             isc_throw(BadValue, "excluded prefix length "
                       << static_cast<unsigned>(excluded_prefix_len)
-                      << " must be lower than the delegated prefix length "
+                      << " must be longer than the delegated prefix length "
                       << static_cast<unsigned>(prefix_len_));
         }
 
@@ -312,6 +319,13 @@ Pool6::init(const Lease::Type& type,
                   << static_cast<int>(delegated_len) << ")");
     }
 
+    IOAddress first_address = firstAddrInPrefix(prefix, prefix_len);
+    if (first_address != prefix) {
+        isc_throw(BadValue, "Invalid Pool6 address boundaries: " << prefix
+                  << " is not the first address in prefix: " << first_address
+                  << "/" << static_cast<uint32_t>(prefix_len));
+    }
+
     /// @todo: We should probably implement checks against weird addresses
     /// here, like ::, starting with fe80, starting with ff etc. .
 
@@ -323,12 +337,6 @@ Pool6::init(const Lease::Type& type,
     // much faster to do calculations on prefix lengths.
     capacity_ = prefixesInRange(prefix_len, delegated_len);
 
-    if (prefixLengthFromRange(prefix, last_) < 0) {
-       // The pool is bad: give up
-       isc_throw(BadValue, "invalid prefix range "
-                 << prefix.toText() << "-" << last_.toText());
-    }
-
     // If user specified an excluded prefix, create an option that will
     // be sent to clients obtaining prefixes from this pool.
     if (excluded_prefix_len > 0) {
diff --git a/src/lib/dhcpsrv/tests/subnet_unittest.cc b/src/lib/dhcpsrv/tests/subnet_unittest.cc
index da0097450b..07e69ab10c 100644
--- a/src/lib/dhcpsrv/tests/subnet_unittest.cc
+++ b/src/lib/dhcpsrv/tests/subnet_unittest.cc
@@ -466,7 +466,7 @@ TEST(Subnet4Test, pool4Checks) {
     ASSERT_THROW(subnet->addPool(pool2), BadValue);
 
     // this one is totally out of blue
-    Pool4Ptr pool3(new Pool4(IOAddress("1.2.3.4"), 16));
+    Pool4Ptr pool3(new Pool4(IOAddress("1.2.0.0"), 16));
     ASSERT_THROW(subnet->addPool(pool3), BadValue);
 
     // This pool should be added just fine.