-adt_nominum=adt
-adt_testbed_ram=256
-adt_freeze_ram=32
-adt_fs_size=3072M
-adt_fs_snapsize=2560M
-adt_fs_cowchunk=8
-adt_playbase=/var/lib/autopkgtest/xenlvm
-adt_fs_type=ext3
-adt_fs_mkfs_args=''
-adt_vm_reduce_retries=10
-adt_ssh_keytype=dsa
-
-adt_debootstrap_components='*'
-adt_debootstrap_include=libc6-xen,openssh-server,ed
-adt_debootstrap_includemore=
-adt_debootstrap_mirrors=''
-adt_debootstrap_script=''
-
-adt_fw_localmirrors=''
-adt_fw_prohibnets='192.168.0.0/24 172.16.0.0/12 10.0.0.0/8'
-adt_fw_allowglobalports='80'
-
-adt_guest_macaddr=00:16:3e:7c:aa:7f
-adt_net_vifscript=/etc/xen/scripts/vif-route-adt
-adt_normaluser=adtxenu
+: ${adt_nominum:=adt}
+: ${adt_testbed_ram:=256}
+: ${adt_freeze_ram:=32}
+: ${adt_fs_size:=6144M}
+: ${adt_fs_snapsize:=5120M}
+: ${adt_fs_cowchunk:=8}
+: ${adt_swap_size:=5120M}
+: ${adt_playbase:=/var/lib/autopkgtest/xenlvm}
+: ${adt_fs_type:=ext3}
+: ${adt_fs_mkfs_args:=}
+: ${adt_vm_reduce_retries:=10}
+: ${adt_ssh_keytype:=dsa}
+
+: ${adt_debootstrap_opts:=}
+: ${adt_debootstrap_components:='*'}
+: ${adt_debootstrap_include:=openssh-server,ed}
+: ${adt_debootstrap_includemore:=}
+: ${adt_debootstrap_mirrors:=}
+: ${adt_debootstrap_script:=}
+
+: ${adt_fw_localmirrors:=}
+: ${adt_fw_prohibnets:=192.168.0.0/24 172.16.0.0/12 10.0.0.0/8}
+: ${adt_fw_allowglobalports:=80}
+
+: ${adt_guest_macaddr:=00:16:3e:7c:aa:7f}
+: ${adt_net_vifscript:=/etc/xen/scripts/vif-route-adt}
+: ${adt_normaluser:=adtxenu}