diff --git a/test.sh b/test.sh
index db1005935dc14f550540912ef644d945e66afbd5..2cb14a34556a812c62f8a0a8fcc44c52cd1438f1 100755
--- a/test.sh
+++ b/test.sh
@@ -9,7 +9,7 @@
 #
 # Configuration is entirely controlled via environment variables:
 #
-# - DIST: select the Debian distribution to use (default "buster")
+# - DIST: select the Debian distribution to use (default "bullseye")
 #
 # - LIBVIRT_USER, LIBVIRT_HOST: use libvirt-over-SSH, needs SSH
 # passwordless authentication to be set up.
@@ -75,7 +75,7 @@ vm_manager() {
 set -eu
 
 # Select the Debian distribution to use.
-dist="${DIST:-buster}"
+dist="${DIST:-bullseye}"
 
 # Choose a random network in the 10.x range.
 ip_net_prefix="10.$(( $RANDOM % 255 )).$(( $RANDOM % 255 ))"