diff --git a/CHANGELOG.rst b/CHANGELOG.rst
index c3cd7089df..3cf7e137d1 100644
--- a/CHANGELOG.rst
+++ b/CHANGELOG.rst
@@ -48,6 +48,8 @@ Fixed
   are parsed properly.
 
   Contributed by Bradley Bishop (@bishopbm1 Encore Technologies)
+* Fix a regression when updated ``dnspython`` pip dependency resulted in
+  st2 services unable to connect to mongodb remote host (bug fix) #4997
 
 Removed
 ~~~~~~~
diff --git a/fixed-requirements.txt b/fixed-requirements.txt
index 84eee50218..58d673c227 100644
--- a/fixed-requirements.txt
+++ b/fixed-requirements.txt
@@ -2,6 +2,8 @@
 # Note: amqp is used by kombu
 amqp==2.5.2
 apscheduler==3.6.3
+# NOTE: 2.0 version breaks pymongo work with hosts
+dnspython>=1.16.0,<2.0.0
 cryptography==2.8
 # Note: 0.20.0 removed select.poll() on which some of our code and libraries we
 # depend on rely
diff --git a/requirements.txt b/requirements.txt
index a45af38863..9b37cadde2 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -11,6 +11,7 @@ apscheduler==3.6.3
 argcomplete
 bcrypt==3.1.7
 cryptography==2.8
+dnspython<2.0.0,>=1.16.0
 eventlet==0.25.1
 flex==6.14.0
 git+https://github.com/StackStorm/logshipper.git@stackstorm_patched#egg=logshipper
diff --git a/st2common/in-requirements.txt b/st2common/in-requirements.txt
index d3856f74cf..03ef106673 100644
--- a/st2common/in-requirements.txt
+++ b/st2common/in-requirements.txt
@@ -1,5 +1,6 @@
 # Remeber to list implicit packages here, otherwise version won't be fixated!
 apscheduler
+dnspython
 python-dateutil
 eventlet
 # used by eventlet
diff --git a/st2common/requirements.txt b/st2common/requirements.txt
index 5db1665b2f..52de391b2f 100644
--- a/st2common/requirements.txt
+++ b/st2common/requirements.txt
@@ -8,6 +8,7 @@
 amqp==2.5.2
 apscheduler==3.6.3
 cryptography==2.8
+dnspython<2.0.0,>=1.16.0
 eventlet==0.25.1
 flex==6.14.0
 git+https://github.com/StackStorm/orquesta.git@v1.1.1#egg=orquesta