diff --git a/zuul.d/ironic-jobs.yaml b/zuul.d/ironic-jobs.yaml
index c59c54e86f..ca17574174 100644
--- a/zuul.d/ironic-jobs.yaml
+++ b/zuul.d/ironic-jobs.yaml
@@ -250,9 +250,9 @@
         # a small root partition, so use /opt which is mounted from a bigger
         # ephemeral partition on such nodes
         LIBVIRT_STORAGE_POOL_PATH: /opt/libvirt/images
-        IRONIC_ANACONDA_IMAGE_REF: http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/
-        IRONIC_ANACONDA_KERNEL_REF: http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/images/pxeboot/vmlinuz
-        IRONIC_ANACONDA_RAMDISK_REF: http://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/images/pxeboot/initrd.img
+        IRONIC_ANACONDA_IMAGE_REF: https://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/
+        IRONIC_ANACONDA_KERNEL_REF: https://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/images/pxeboot/vmlinuz
+        IRONIC_ANACONDA_RAMDISK_REF: https://mirror.stream.centos.org/9-stream/BaseOS/x86_64/os/images/pxeboot/initrd.img
         IRONIC_ANACONDA_INSECURE_HEARTBEAT: True
         IRONIC_DEPLOY_CALLBACK_WAIT_TIMEOUT: 3600
         IRONIC_PXE_BOOT_RETRY_TIMEOUT: 3600