Here are the interesting bits from the log: 1 LOADPARM=[........]^M 2 Network boot device detected^M 3 ^M 4 Network boot starting...^M 5 Using MAC address: 52:54:00:02:a3:f9^M 6 Requesting information via DHCP: ^H^H^H010^H^H^H^Hdone^M 7 Using IPv4 address: 192.168.122.102^M 8 Using TFTP server: 192.168.122.1^M 9 Bootfile name: 'boots390x.bin'^M 10 Receiving data: 0 KBytes^M 11 TFTP error: file not found: boots390x.bin^M 12 Trying pxelinux.cfg files...^M^M ... 14 TFTP: Received s390x/01-52-54-00-02-a3-f9 (581 bytes)^M 15 Loading pxelinux.cfg entry 'execute'^M ... 17 TFTP: Received ubuntu/s390x/ga-19.04/disco/daily/boot-kernel (4318 KBytes)^M ... 19 TFTP: Received ubuntu/s390x/ga-19.04/disco/daily/boot-initrd (19360 KBytes)^M 20 Network loading done, starting kernel...^M 21 ^M 22 [ 0.439873] Linux version 5.0.0-38-generic (buildd@bos02-s390x-020) (gcc version 8.3.0 (Ubuntu 8.3.0-6ubuntu1)) #41-Ubuntu SMP Tue Dec 3 00:26:40 UTC 2019 (Ubuntu 5.0.0-38.41-generic 5.0.21) ... 38 ^M[ 0.451953] Kernel command line: nomodeset ro root=squash:http://192.168.122.1:5248/images/ubuntu/s390x/ga-19.04/disco/daily/squashfs ip=::::vm1:BOOTIF ip6=off overlayroot=tmpfs ov erlayroot_cfgdisk=disabled cc:{'datasource_list': ['MAAS']}end_cc cloud-config-url=http://192-168-122-0--24.maas-internal:5248/MAAS/metadata/latest/by-id/wpr3yp/?op=get_preseed apparmor =0 log_host=192.168.122.1 log_port=5247 --- console=tty1 console=ttyS0 BOOTIF=01-52-54-00-02-a3-f9 ... 155 Begin: Mounting root file system ... Begin: Running /scripts/local-top ... IP-Config: enc1 hardware address 52:54:00:02:a3:f9 mtu 1500 DHCP RARP^M 156 hostname vm1 IP-Config: no response after 2 secs - giving up^M 157 IP-Config: enc1 hardware address 52:54:00:02:a3:f9 mtu 1500 DHCP RARP^M 158 hostname vm1 hostname vm1 IP-Config: enc1 complete (dhcp from 192.168.122.1):^M 159 address: 192.168.122.102 broadcast: 192.168.122.255 netmask: 255.255.255.0 ^M 160 gateway: 192.168.122.254 dns0 : 192.168.122.1 dns1 : 10.245.236.13 ^M 161 domain : maas ^M 162 rootserver: 192.168.122.1 rootpath: ^M 163 filename : lpxelinux.0^M 164 :: root=squash:http://192.168.122.1:5248/images/ubuntu/s390x/ga-19.04/disco/daily/squashfs^M 165 :: mount_squash downloading http://192.168.122.1:5248/images/ubuntu/s390x/ga-19.04/disco/daily/squashfs to /root.tmp.img^M 166 Connecting to 192.168.122.1:5248 (192.168.122.1:5248)^M 167 ^Mroot.tmp.img 21% |****** | 66726k 0:00:03 ETA^Mroot.tmp.img 98% |****************************** | 296M 0:00:00 ETA^Mroot.tmp.img 100% |*******************************| 301M 0:00:00 ETA^M 168 :: mount -t squashfs -o loop '/root.tmp.img' '/root.tmp'^M 169 done. ^^ all of this seems to be the initial deployment ^^ We see curtin doing its things as instructed by maas. Later on we see the reboot after install then 1362 -----END SSH HOST KEY KEYS-----^M 1363 [ 202.776296] cloud-init[1567]: Cloud-init v. 19.3-41-gc4735dd3-0ubuntu1~19.04.1 running 'modules:final' at Mon, 10 Feb 2020 10:42:08 +0000. Up 114.97 seconds.^M 1364 [ 202.776472] cloud-init[1567]: Cloud-init v. 19.3-41-gc4735dd3-0ubuntu1~19.04.1 finished at Mon, 10 Feb 2020 10:43:36 +0000. Datasource DataSourceMAAS [http://192-168-122-0--24.maas-i nternal:5248/MAAS/metadata/curtin]. Up 202.74 seconds^M 1365 [^[[0;32m OK ^[[0m] Started ^[[0;1;39mExecute cloud user/final scripts^[[0m.^M 1366 [^[[0;32m OK ^[[0m] Reached target ^[[0;1;39mCloud-init target^[[0m.^M 1367 [^[[0;32m OK ^[[0m] Stopped target ^[[0;1;39mGraphical Interface^[[0m.^M 1368 [^[[0;32m OK ^[[0m] Stopped target ^[[0;1;39mCloud-init target^[[0m. ... 1487 [^[[0;32m OK ^[[0m] Reached target ^[[0;1;39mReboot^[[0m.^M 1488 LOADPARM=[ ]^M 1489 Using virtio-blk.^M 1490 Using SCSI scheme.^M 1491 .....^M 1492 [ 0.412847] Linux version 5.0.0-38-generic (buildd@bos02-s390x-020) (gcc version 8.3.0 (Ubuntu 8.3.0-6ubuntu1)) #41-Ubuntu SMP Tue Dec 3 00:26:40 UTC 2019 (Ubuntu 5.0.0-38.41-generic 5.0.21) ... the rest is the startup until a login: 1967 vm1 login: But this does NOT use "fallback from failed network boot". It used a valid netboot (into the deployment) and then reboot