diff --git a/lower-constraints.txt b/lower-constraints.txt
index d51901979e..5bd71d4038 100644
--- a/lower-constraints.txt
+++ b/lower-constraints.txt
@@ -84,7 +84,7 @@ oslo.context==2.19.2
 oslo.db==4.27.0
 oslo.i18n==3.15.3
 oslo.log==3.36.0
-oslo.messaging==5.29.0
+oslo.messaging==6.3.0
 oslo.middleware==3.31.0
 oslo.policy==1.30.0
 oslo.reports==1.18.0
diff --git a/requirements.txt b/requirements.txt
index fb25bd337d..c08fbdb97c 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -21,7 +21,7 @@ oslo.context>=2.19.2 # Apache-2.0
 oslo.db>=4.27.0 # Apache-2.0
 oslo.i18n>=3.15.3 # Apache-2.0
 oslo.log>=3.36.0 # Apache-2.0
-oslo.messaging>=5.29.0 # Apache-2.0
+oslo.messaging>=6.3.0 # Apache-2.0
 oslo.middleware>=3.31.0 # Apache-2.0
 oslo.policy>=1.30.0 # Apache-2.0
 oslo.reports>=1.18.0 # Apache-2.0
diff --git a/tox.ini b/tox.ini
index 7ba665267b..0c1ea8dd95 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,9 +8,10 @@ usedevelop = True
 setenv = VIRTUAL_ENV={envdir}
          PYTHONWARNINGS=default::DeprecationWarning
 install_command =
-    pip install -U -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt} {opts} {packages}
+    pip install {opts} {packages}
 whitelist_externals = find
-deps = -r{toxinidir}/requirements.txt
+deps = -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+       -r{toxinidir}/requirements.txt
        -r{toxinidir}/test-requirements.txt
 commands =
   stestr run {posargs}
@@ -21,7 +22,7 @@ basepython = python3
 # This environment is called from CI scripts to test and publish
 # the API Ref to developer.openstack.org.
 deps =
-    -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/doc/requirements.txt
 whitelist_externals = rm
@@ -86,7 +87,7 @@ whitelist_externals =
 [testenv:docs]
 basepython = python3
 deps =
-    -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/doc/requirements.txt
 whitelist_externals = rm
@@ -156,7 +157,7 @@ max-line-length = 79
 [testenv:releasenotes]
 basepython = python3
 deps =
-    -c{env:UPPER_CONSTRAINTS_FILE:https://opendev.org/openstack/requirements/raw/branch/master/upper-constraints.txt}
+    -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/doc/requirements.txt
 whitelist_externals = rm