diff --git a/testing/testing.conf b/testing/testing.conf
index 335957732..683b3dfbd 100644
--- a/testing/testing.conf
+++ b/testing/testing.conf
@@ -48,7 +48,7 @@ fi
 
 # Base image settings
 # The base image is a pristine OS installation created using debootstrap.
-: ${BASEIMGSIZE=1800}
+: ${BASEIMGSIZE=2500}
 : ${BASEIMGSUITE=stretch}
 : ${BASEIMGARCH=amd64}
 : ${BASEIMG=$IMGDIR/debian-$BASEIMGSUITE-$BASEIMGARCH.$IMGEXT}