diff --git a/.github/workflows/oci.yml b/.github/workflows/oci.yml
index 5b545461e5..31614b8f38 100644
--- a/.github/workflows/oci.yml
+++ b/.github/workflows/oci.yml
@@ -9,7 +9,7 @@ on:
 
 jobs:
   phpunit-oci8:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
 
     strategy:
       # do not stop on another job's failure